in the the dirty south where i am from, Texas, the thugs and gangstas do th is as a way to show that they have money, status. The same thing as wearing big daimons in ears, or rolex watches. The same as having an old school big body cady on 22 inch chrome wheels with woodgrain and leather interior.
Its just gangsta.
I know for one that my brothers with the silver and princess cutts, and having the mold done, was just over a grand between t he top and bottom.
also i have seen a lot that are worth 10k, 13k, 25k, 30k, 40 grand.
THEY DO SLIDE ON AND OFF. Mostly though i think its just a thug thing, and if you come from a private or prep school around lake minitonka with a senior class of 36 and listen to d.m.b. and incubus all day while playing cs... it wont make sense to you.