I remember when you could smoke in any shops, McDonalds, cinemas etc.,any public place, and they had ashtrays. In them days it was unthinkable to deny a smoker the right to smoke anywhere, so, accurate Columbo behaviour for the times.
All joking aside, maybe it was just the word "ashes" in that title that threw you.
After all, Milo has those two really good lines about Columbo's "cigar ashes."
I also am not a cigar fan, so I sympathize with the characters who are irritated by Columbo’s smoking, especially when he is careless or inconsiderate with the ashes. Yuck.