I say thank you a lot. Sometimes sarcastically. Sometimes because it ends a conversation I don't want to be in nicely. Sometimes cause I'm talking to myself... but if you're really conscious of those two words, it'll amaze you how many times you say it sincerely. I always make it a point to say thank you at the drive through speaker... There are a couple places in town that say... "your welcome!" which is nice, in a way- however, shouldn't they be thanking me too?