I recently bought a longish thin knit sweater that came with a thin belt. The belt gives the sweater a nice shape. There are very thin “belt loops” sewn into the sweater - a single loop of string on each side. Now my question is am I supposed to actually use these belt loops or do I just wear the belt loose and cut the loops off?
My understanding has always been that they are there simply to hold the belt in place/keep it together with the garment while the garment is on the rack in the store. I always cut them off before I wear it.
Same thing with garments that have thin straps or are strapless - the longer loops that go over the hanger, to keep the garment from falling off the hanger while it is in the store. I cut those out too.
It depends on whether the loops are where you’d wear the belt or not. If they’re not, cut them off; if they are, use them. Different people will want the belt at different heights; the designer assumed that people that particular size would want it at a particular spot but, depending on their exact shape and on what effect they want to achieve, they may not.
What Nava said. If they’re not where you’d like the belt to sit then cut them off, but if they are and actually serve the purpose of keeping the belt in place, then it’s certainly not gauche to leave them.