I think you are catching on....
The $30 my wife spent for Half Life in Christmas of '98 has bought countless hours of gaming enjoyment for nearly 5 years
An excellent investment.
Over that course of time there have been numerous free updates for CS as well as quite a few other mods.
Yes, steam will ultimately become the vehicle by which they will seek to charge us for playing 'their' game online, either by a large one-time fee or a monthly amount. Steam is not yet mandatory to play the half life mods online... THESE are the good old days.
Regarding updating your steam account, I believe there may be an option under "settings" in which you can change your account. Failing that, you may have to uninstall steam in the control panel and then reinstall it (There is no uninstall routine bundled with that software).
As someone who has become intimately familiar with half life/cs/won over the past five years by daily playing and running a dedicated server, I see nothing cool or convenient in running steam. I personally know of a number of avid players who will be knocked off the playing field either because their computers won't handle steam or they are not sophisticated enough to get it working. I am certain that there will be thousands facing that predicament worldwide.