Of course noone should require steam to have and play a game. actualy, games that require aren't actualy needing you to start steam , there is always offline mode and many games can be started from their folders. one needs steam for downloads and updates though.
Steam has many good things speaking for it.
It ofers great benefits to developers who sell directly, without needing to pay 30% or more to publishers.
Benefit of automatic updates and always available downloads, and there is a way of having same games on several comps.....
Definitely beats EA and ubisoft idiotic DRMs....I just know if you announce that you will offer steam keys to backers, you would draw more....also, one way would be to offer preorders open beta access.....many do that and have great success - fallen enchantress and sequel, legendary heroes. Fantastic sequels to Masters of Magic..