I have begun to like, more and more, trousers wihtout belt loops, but do not have these in abundance at the moment. There are two reasons: 1. I live in the tropics, where odd trousers, shirt and tie are standard CBD, and odd trousers generally do not come off the rack with side adjusters (there are some brands; it's just not common); and 2) my weight has fluctuated a bit this year and, with it, my waistline. I'm not sure I could keep my pants up without a belt!
Tha being said, they do form a cleaner line, and tend to come across, even if you are not a clothes junkie, to be special.