I like playing games regardless of what system they originally released for. I hope every PS3/360 game gets a remaster. I know they won't, but it would only increase my gaming library.
My number one most desired update to the PS4 is support for PS1 and PS2 games. I, like most gamers I imagine, do not get to play every good game that comes out during a given console's life cycle, and I'm always happy to have the opportunity to go back and play games that I missed out on.
I certainly understand and agree with the frustration at relatively unimpressive up-ports and high initial pricing, especially compared to some of the great bargains that were offered on PS3, however the price eventually comes down and as a consumer I am free to pick up the game when it reaches a price point that I consider compelling.
I won't get Saints Row 4 or God of War 3 or even these Batman games at a steep initial price, but I will probably get them when they cost less than $20 down the road.