"I really don't like the fact that I need to have other games to get cool bonus stuff in a completely different game."
It's free stuff as a thank-you for purchasing other titles owned by EA. It's not a necessary part of the game, and they didn't have to do anything at all. I think it's very cool to be rewarded for playing other games. When DS2 was released, DA2 players got Issac's armor in DA2. ME2 players got DA:O's Blood Dragon armor for playing Dragon Age: Origins. You can say what you like about EA's DRM and Project $10 policies - their franchise support is outstanding.
(KOTOR excepted, of course)
