Cannabis use is a lot more prevalent than a lot of people realize. I know a lot of people who use cannabis and most don't smoke it. Most that do smoke do it in vapor form. The only people that I know that still smoke weed by burning it and inhaling the smoke are mainly the stereotypical potheads. I think cannabis use is much much safer than alcohol consumption.

This is just my personal experience but those that can use cannabis, with out getting in trouble at work, and are heavy drinkers will heavily decrease their alcohol consumption and in some cases give up alcohol altogether.