I wear them with every day, with suits, as I've been doing for at least the last 20 years. Have about 25 pair, which is down from the peak of about 10 years ago; had probably 50 pair back then. Thurston's (the special ones designed by Mimmo Spano) and Trafalgar Special Editions mostly.
I wear belts with odd trousers, though sometimes I'll also throw on a pair of braces w/those too. As has already been said and echoed several times, they just do a better job of holding your pants right where they should be.