Personally, I see software piracy as a marketing/sales problem: instead of asking "How can we get them to stop stealing our stuff?" they should be asking "How can we get them to buy our stuff?"
Point being, this kind of thing is going to happen - these sites are going to come down, be it for legal, business, or hackery reasons. They are not safe for long-term use. Read up about
The Archive Team to learn about the importance of institutionalized backups and archiving, and the danger of "the Cloud".
I've seen users here at Amiga.org post files to Megaupload and similar sites: programs they've written, scripts they've created, images they've made, formerly commercial software reclassified as freeware, document scans. All that stuff is lost now. Aminet is our best repository for preserving Amiga goodies.