If it's successful then enough people obviously don't feel it's a "rip". You can be bitter and call them stupid or sheep or whatever but the fact of the matter is everyone spends money on something that others would deem foolish.
I myself pay $30 tops per year for online play, cross game invites, voice messaging, party chat, global mute ability, join session in progress, unified features across all games and voice quality that isn't god awful. Sure, you can say "well durr this has been free on PC for years". Who gives a fuck. That's the PC. And secondly, no, it's not available in one tight little package like this anywhere else. That's a convenience. And people will pay a premium in any market for a convenience. It's been this way forever.
As for the rise of DLC, I think the rise of development costs and economy are just as much to blame there as "stupid people".