Lifetime memberships to what though? Generally they pay for 'free' versions of a particular program such as LimeWire or FrostWire or ShareAza, etc. 'Sometimes' the site has a copy of LimeWire Pro, though that's not very common. So they are paying lots of money for something they can get for free in most cases.
The sites will still be out there as you suggested. And besides that, many of these scam sites change physical location as well as perhaps web location to get away from the authorities who might be getting too close to them.