[bmxicle]

Only read about half the posts so sorry if this has been covered.

I think it's quite reasonable to say that as wealth increases people will tend to tip more. This isn't a firm rule, but i think it is generally true. So the states has been continually prosperous for a long time, and thus an increase in tipping wouldn't be all that unreasonable. I also think this is partly your perception of it as when you were in college i'm guessing you were significantly poorer then you are now, and probably went out to dinner with poorer people and thus the "standard" tip was much lower like 10-15%. However, as you got older and you and your friends accumulated wealth you all would have started tipping more. So i think American prosperity has something to do with it, but i also think the increase in your wealth has even more to do with your perception of the incredibly important 2p2 issue of tipping. This is a rather extreme example but if you compare my wealthy poker playing friends, to my college friends you'll see an average tip of like 25% compared to like 5%, and it all has to do with wealth.