I've joked before that I am GM Brainwashed
However, I can't say how much of that is due to four years on a GM sponsored team and how much is due to growing up in a GM family (At least four immediate family members have worked/do work for GM, nifty employee discount thing).
Other things, I'm often biased towards FIRST sponsors (ex - I need some lunch, I think I'll buy from Restaurant A who donated to the team as opposed to Restaurant B who did not).