You are correct. It is now illegal to have an ashtray anywhere in any "workplace" (yes, even your own home, if, say...you are having a party and hire a caterer to serve food to your guests).
While I have not heard of anyone being fined for having ashtrays in a private home even if it is a "workplace," I do know that people HAVE been fined for having empty, clean ashtrays, tucked away in drawers in offices.
Scary, ain't it?
Regards
PS: GREAT remarks to the St. Louis City Council, BTW.
Your choice...