Congrats, Germany, on doing the right thing. If tobacco and alcohol are legal, weed absolutely should be as well.
It's been legal in Canada for a few years now and society hasn't crumbled as a result. All it means is more tax dollars, less organized crime, and less people being thrown in jail for using a relatively harmless substance.
Note: I don't use myself, it's just a no-brainer to legalize it.
When it comes to the tax dollars however, you can get sleeze-balls like Doug Ford's Conservatives and put the funds in the general account and continue to underfund Healthcare and Education.