Actually, "Thank You" button can work if mods make it so that only the person being 'thanked' can see who thanked him for what and how many. No one else gets to see the amount of thanking since there is no point.

If the person getting thanked isn't the high and mighty type, he will be happy with the thanks themselves. Also, I don't see anyone posting "I got so many thanks" in an argument because you know how THAT will make them look like. :P