That'll likely be the entire gamut of guys who aren't doing drag or masquerading. For instance, the ones who are completely fed up with the bilge that's being foisted upon us as "choices" in attire, those who happen to like the feel and sensation of "nice" fabrics, and those who just like being a little bit different. Note that there's a lot of overlap in there, so don't try LASERing in on only one aspect.
Note that I personally detest the use of the term "crossdress" simply because it's a lopsided term that applies only to the male of the species, and usually in a pejorative manner. We need to expunge it -- and it's tarted up Latinate twin -- from our vocabulary.