I don't usually apologize for most things - usually because I am not sorry for what ever it is. I do find it annoying when people apologize/use apologizing language for things which they had nothing to do with, are not really sorry, or are just saying it because it seems like they want to be reassured without directly saying so. It has always seemed a bit passive/aggressive to me.
I do find hearing about those of you who do it useful because it helps me not have such a strong negative reaction to those in my life who do it and to have more patience with them.