You are leasing the track but there are no problems transferring songs, its very very easy just put you Apple account on another machine and download all you tunes directly from them again at no extra cost. The only limitation is if you want to burn them to a CD you can only do that a limited amount of times, but you can transfer them to iPods/MP3 players as many times as you want.
As for "rip off," well suppose it works like this. When iTunes first started it offered bargains that very aggressively undercut the high street. Now most of the big chains have gone bankrupt and HMV is on its last legs, they have started selling albums at pretty much the same price as the high street did because they are the market leader. Although to many of us music fans it seems perverse to buy a album for the same price as HMV without the CD, box, artwork and lyrics book, many of iTunes customers prefer this. No clutter in their houses!
I think the biggest problem is quality. The iTunes MP3 quality is just slightly worse than CD if played through a decent sound system. Playing them through iPod phone or PC speakers that most people use these days and you wont notice the difference though. They keep going on about so called "HD audio" will come in eventually but so far it hasn't really happened and I can't see it doing so cause Joe public doesn't give a toss, sadly.
I personally feel a bit sorry for the remaining high street record stores as we've possibly evolved or perhaps devolved to a stage where people aren't bothered how good a boxed release is; be that in terms of audio quality or what you get in terms of packaging. Add piracy to the mix and they don't stand a chance anymore really.