A) I have brains, and still had issues.
B) Because there is a major difference between the two and it isn't the software(I agree its the same software). It is the authentication that steam uses to verify that the software is legit. This is what causes an huge number of issues. This is not C2 related at all, this is steam related. And steam is aware of it and couldn't care about fixing it. I spent some time in correspondence with them, they truly don't give a sh*t.
Steam and C2: Yes it works, for awhile, but depending on your pc, your installed software, your drivers, your everything it can break on a single update from anything.
Steam version: Crashed every couple hours, was less productive than standalone (multiple instances, file association etc)
Standalone version: ZERO ISSUES.
The authentication imho is more then fine, it works as it should and that is how it should be.
I cant verify any of the problems you have had with the Steam version.
And what should Steam fix? It works as it should.
It may be, since there was a few months where C2 in general had editor crashing bugs, it may be that you used the Steam version in exactly that time period.
But in the end, it comes to one point, the choice. Everyone has to choose for himself what is working what not, try the Free steam version, see if it works,
if you like Steam, use it, if not, don't. So yeah, just as spacedoubt said, in the end, it is your choice alone.