Yea, I know how you feel but not really. I'm a huge physical copy buff. I didn't want to buy MP3 on disc at retail price because I knew I wouldn't want to play it knowing the Steam version had Steamworks.
Luckily Amazon had a great deal where it was priced at $30, it is still on sale but for $40 now, which I find weird I guess it was selling too well or they messed up and priced it too low.
But one day when the price is right I will buy the physical copy for that one day Steam goes down or I don't have internet connection.
Plus I get no cd cracks for all my games because I deserve that right.
But to go back on topic, here is a link with all games that use Steamworks:
http://forums.steampowered.com/forums/s ... ?t=1712878
It tells you what games use Steamworks and whether the physical or retail copy can be used and activated on Steam.
Same thing goes for L.A. Noire which I snagged the complete edition for $7.50 a few weeks ago as well. The retail copy is basic DRM while the Steam version uses Steamworks.
So check that site and don't let it happen again lol. I've noticed quite a few games have been on Steam for download only, or only the download has achievements.
I'm waiting for Reckoning: Kingdoms of Amalur to go down in price on Steam to get those achievements, and the Witcher 2, too. Have the retail copies, but those can't be registered on Steam.