Succumbing to a vice or weakness and wanting to make it common is two different things.
For instance a homosexual can still see it as not something to be promoted and advanced in a society.
A guy who has a vice of gambling on Saturday night doesn’t have to be pro-gambling in legislation politics.
Someone who hates and fears guns doesn’t have to base his political position on that.
True, I suspect you don’t see heroin addicts going around telling people...”You gotta try this stuff, it’s great!”