[Ghunger]

The grease would definitely work but I bet there's something you could DIY to act like that spacer they're selling. It would be a lot cleaner than the grease and probably wouldn't cost much. You might also be able to paint the mating surface of the wheel to keep it from getting stuck. You'd have to be careful preparing the surface (cleaning and roughing up the wheel) or else the primer and paint won't stick well. Just a couple ideas.