Even attendees at Canada’s biggest cannabis trade show, Lift, on this weekend at Metro Convention Centre, had mixed feelings about legalization, with some worried government control and corporatization would crush the little guy.

Longtime head shop owner Luke Reynolds sees recreational marijuana in Canada eventually rolling out “like Tim Hortons and Starbucks” on every corner.

“It will be government run and I think they’re going to crush all the little guys like us who started this movement in the first place,” said Reynolds, owner of PipeDreamz in Ajax, while selling his vaporizers and pipes for pot smokers at Lift, Canada’s biggest cannabis convention, Saturday in Toronto.

Most medical cannabis advocates can name one key moment in their life when they knew they had to come out of the closet and campaign for regulated, legal access to the cannabis plant.

But there is also a clutch of extraordinary individuals who, when confronted with real evidence about the cannabis plant’s therapeutic potential, have done a 180 degree turn, transforming themselves from herb hater to cannabis campaigner.

1. The Doctor

Dr Sanjay Gupta, chief medical correspondent for CNN, is perhaps the most high profile cannabis critic to come out in favour of the plant. 

Considering how unpopular marijuana was with the public during the mid-1990s, it's phenomenal to take a step back and witness just how rapidly pot's presence has grown in the United States over the past 21 years.

Marveling marijuana's expansion

In 1996, California became the first state to legalize the use of medical cannabis for compassionate use. Since California, 27 additional states and Washington, D.C., have followed. Five new states legalized medical weed last year alone, including Pennsylvania and Ohio, which chose to do so entirely through the legislative process.

Uruguay has become the first country to completely legalise cannabis.

The country became the first place in the world to permit the professional cultivation of marijuana plants in 2014 and from July new legislation it will be legal to sell it over the counter.

The move will make it the first country in the entire world where anyone can buy or sell the drug.

In countries who are more famous for their lax approach to cannabis, such as the Netherlands, the drug remains technically illegal even if the law is not enforced and local authorities will grant licences to shops and cafes selling it.

Adding cannabis to everything from iced coffee to breath mints, local startups are jockeying for a bite of California’s growing marijuana edibles market as the state gears up to allow recreational pot sales.

The industry that barely existed 10 years ago — apart from a few bakers making pot brownies in their home kitchens — now shows no sign of slowing down.

“There’s a brand boom going on right now, particularly in preparation for adult use legalization here,” said Troy Dayton, CEO of The Arcview Group, a research and investment services firm focusing on marijuana businesses. “Not all of them are going to do well, but there’s just so many different types of edibles hitting different market segments.”

Now that marijuana has been legalized is so many states, and is about to become legal across Canada, new concerns have been raised over people driving or being on the job while impaired by recent marijuana use. Well, those concerns are being addressed.

Like the familiar breathalyzer used to test whether a driver is behind the wheel while impaired by alcohol, a similar hand-held device that tests for recent marijuana use is already being tested in Canada and the United States, including a small device being tested in California that uses a small sample of saliva to test for six drugs within minutes.

Colorado's two U.S. Senators are leading a new bipartisan effort to provide banking for marijuana businesses.

Democrat Michael Bennet and Republican Cory Gardner are co-sponsors of the legislation.

“The lack of access to banking services for marijuana businesses is a key issue in Colorado,” Bennet said.

“It raises significant public safety concerns for both employees and customers of these businesses and creates compliance and oversight challenges. This common-sense bill would address those issues by allowing our banking system to serve marijuana businesses that are in compliance with state laws.”

There's no doubt marijuana businesses are a target for criminals. In the past 18 months, L'Eagle Cannabis Gallery in Denver has been burglarized three times.

The Legislature has given preliminary approval and may soon send to Gov. Paul LePage a bill that funds and designates the agency that will administer recreational marijuana sales in Maine, approved by voters at referendum in November.

The bill gives the Bureau of Alcoholic Beverages and Lottery Operations the authority to oversee recreational marijuana use. That’s a change from the measure approved by voters, which would have given regulatory authority to the Department of Agriculture, Conservation and Forestry.

Economic advisors in Oregon have released their first estimate of what the state will make taxing marijuana sales. As in Colorado and Washington, the numbers are large and growing.

By the end of 2017, the state expects to have brought in as much as $67.2 million in marijuana taxes. That number is expected to grow to more than $156 million from 2017 to 2019, giving the state more than $210 million to distribute from marijuana tax coffers.

It also means that those who have invested in the marijuana industry are doing well.

Recreational marijuana use has now been legal in California for six months and counting. On the surface, you’d never know that anything has changed. Since the passing of Prop. 64 in November, there have not been red-eyed, burnout bohemians strewn across the lawns of Griffith Park, nor masses of wasted youth in irreversible states of hysteria. Instead, on a hot Saturday afternoon in May, a group of lithe twenty-somethings clad in the kind of spandex that doesn’t leave much room for snacking gathered on a rooftop in the shadow of the Hollywood hills to practice yoga, and get high.