Personally, I've played the games multiple times just fine. Twice it's given me a blue screen, resulting in complete computer reboot. Somewhat alarming, but by no means crippling to gameplay.
It's simply not possible these days to release software which is completely bug free simply because of the wide range of systems, drivers, software etc that are out there. Look at the MMRPG market for a prime example of this. Each MMRPG releases a patch ~once a month and its rare for a patch to not result in a bug on someone's computer.
Realistically, bugs like the diplomacy bug (of which there aren't many) should be taken account of, but CTD bugs etc should not because they are wholly dependant on what system you run (and okay you may be experiencing bugs, but chances are you are an unlucky 1 in 1000).
That's not to say compatability bugs should not be fixed; just that they should not be unexpected.