They've already put prices up once, but are still supremely affordable for a "fire and forget" backup service.

Sure, you can probably do it cheaper with your "friend with a hard drive" solution, but there's zero redundancy there, you'll need to replace the hard drive when it eventually goes bad etc. etc.

For some people that's a tradeoff worth making, but for me, a few extra $ a month for peace of mind is worth it.