Fleetwood gave him that little flag back in Hunter's Moon chapter 6.

One thing I haven't quite found a graceful way to state outright in the comic is that the big drawback to spray-on clothing (besides not being able to replicate the full range of properties and behaviors of woven fabrics, leather, etc.) is that they aren't very durable. They do all right for a day or so, but can't stand up to heavy wear, and after a couple of days they just kinda start to disintegrate. Which is what's happening to Linton's pants.