They’re tainted by the events that happened there. Not by having some shitty thing named for them.
According to this site, the term was first used in Uganda, a former British colony/protectorate. English is one of the official languages of the country and there is a local dialect of English there.
Actually, given the age of the term, the town may be named after the product. 
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Newport News, Virginia and Winston-Salem, North Carolina: I think of cigarettes before cities.
Pall Mall and Great Marlborough Street in London: same thing.
Malibu, California, namesake for the mid-end Chevrolet Malibu.
Watergate Hotel
Not a place, but someone just pointed out to me the rather unfortunate name of… The Oscars.
The inverse of the OP, where a thing is tainted by a place name - several years ago there was a movement among some to change it to ‘Freedom Fries’.
Columbine is a flower, not a place. There’s no city of Columbine.
Presumably the town was named after the mineral, not the other way around. From wikipedia:
The Greek island of Lesvos comes to mind; I don’t consider that a taint but I understand they do.
Errr… Lesbos
Either or. The official transliteration of the Greek name is Lesvos, and it is pronounced “Lezvos”, even though the third letter is a beta.
Toilet water.
Ignorance fought, thanks.
So why is it not “lesvian”?
German fried potatoes have been home fries since 1917.
A very good Greek restaurant in New York is called Molyvos, which is a town on Lesvos, and their menu (last I was there) mentioned their food was Lesvian.
The letter β only started being pronounced /v/ in the standard dialect recently (well, “recently” considering the language is several thousand years old).
The welcome sign for Intercourse is large and heavy, apparently to discourage drunk college students from stealing it again.
Winstons, Salems, Marlboros, and I assume Virginia Slims are named after those places. I think of cigarettes when I pass the exit for Upper Marlboro, MD, but apparently the town is named after the Duke of Marlborough and thus is probably only indirectly related to Marlboro cigarettes.
“It ain’t heavy. It’s my Intercourse-Buddy.”