Barb is completely correct -- the so-called "belt loops" on kilts began life as loops for the sporran belt. If you look at any older kilts (older than 50 years, I would guess here, based on personal experience and examining *a lot* of older kilt) you won't see any belt loops at all.

And, unless I am mistaken, regimental kilts still have no belt loops.

The sporran loops were added sometime within the last 50 years, I would assume. I altered a kilt for a gentleman a few months back that was probably 30 to 40 years old (the kilt, not the gentleman). It had sporran loops that were about 1.5" wide, because they simply were not meant to accomodate a wide kilt belt. They were meant only for the sporran strap.

And just like Barb said, most men don't even need those. Only if you have no hips to speak of would you have to worry about your sporran sliding down (or if you are wearing your sporran belt too loose).

People started to think these loops were for the main kilt belt, so the kilt makers accomodated and made them wider. Now they come standard on most civilian kilts, just because people expect them. But I know a good number of kilt makers who still prefer not to put them on.

I don't put them on any kilt I make unless the client specifically asks for them. Probably less than 5% of the kilts I make have belt loops.

Aye,
Matt