This is my personal idea about the row over cannabis.
Cannabis should be legalised if the benefits of it being legal outweigh the risks (i.e mental health issues)
Some people like it, some don't.
If you could just walk into a supermarket and buy it, it would be in perfect condition just like alcohol and cigarettes. But with drug dealers, you don't know where the stuff has been and what condition it's in.
If it were legal the government could charge duty on the sale of cannabis, which they could put to good use.