I was leary about getting into Steam, when I started on it (maybe a year ago ... I don't know) ... but there are parts I love about it.
I love that I do not have to keep track of discs or game links and such, to have access to the games I've purchased.
Usually around once every two years something sneaks on to my computer that is bad enough that cleaning it up just doesn't seem to work, and the best option is to wipe the entire system and start over again. And then it is a big hassle to manage to find the discs for all of my old, beloved games, and manage to reload them again. With Steam, all I have to do is manage to remember one name and password or what-have-you, and I instantly (well, nearly) have access to all my games again ... or at least all that are on Steam.
RCT3, I bought a copy from Atari's online store something like 6 years ago. And every year or two, I would have to pull out the online installer from the e-mail I received it in, and reinstall. And that was fine ... until a year ago, when it would no longer work. Thankfully, either Atari or Frontier (I'm not sure which, I contacted both) was kind enough to throw me a Steam key for it, and I'm still able to reload and play one of my favorite games.
Other games that I already own (Railroad Tycoon, Tropico), I gladly buy again, if I run across an inexpensive bundle with them in it, just so that I have that easy access.
So understand, I like several things about Steam, and do hope to eventually have PC on Steam, for easier reinstallation ... but if Frontier wants to keep some of their content themselves, to make it available to a wider audience, I have no problems with that, whatsoever! More power to 'em! Steam is neither the enemy, nor your (as a game developer) dearest friend ... they are another company with which to do business with, with all the positives and negatives that always entails!