Hardly the same thing
For the tenner a month Spotify subscription I'd have been pushed to get a whole album of DRM infested nonsense from iTunes, which i would struggle to get to play across all my devices. Spotify works on my phone and all my computers, which is all the devices I need, and I probably listen to at least 5 new albums a month for the money.
Sure I'm paying for something I can't keep afterwards, but that's an explicit part of the deal, and is basically why it only costs a fifth of the money for a service that's actually more convenient than torrenting. And I'm getting to actually feel like I'm paying my way, which makes me feel all warm and fuzzy inside
If the market implodes in the end and I have to go out and buy a load of tracks that I only have on spotify now that will suck, but I'll probably only buy a small proportion of the ones I would have had to buy just to sample without spotify, and by then they'll all be at bargain bin prices.