I don't think that you can generalize about gay hotels any more than you can about straight ones. Certainly there are some that might fit your description, but most would probably be completely non threatening.

I can recall a place called "The Golden Bear" in Amsterdam, recommended by a close, well-travelled friend. Nevertheless, the name conjured all sorts of images. When I checked in, I found fresh flowers and candy at the desk, my room was immaculate, and a breakfast that kept me going until mid-afternoon.

On the other hand, there was a horror story posted here (I think) recently, where a gay hotel in Montreal turned out to be pretty much as you described.

Unfortunately there's no way to know for sure, but in general, the website and the cost per night should be good indicators.