A look at any older home for even the early part of the 20th century, shows how many fewer clothes (of all sorts) our ancestors owned. When you're talking about Scotland from an even earlier period, I'm sure the numbers would be small--even for the wealthy. The wealthy, by the way, would probably have owned at least a couple of pairs of breeches--for riding, etc.

I'm sure different times, places and social levels would dictate how many kilts a man would have--even today!