I think you really want to be playing HU in a tournament situation where you don't get every hand raked--for exactly the reasons you mention.

At the casino where I play, you can also buy the table for $5 per player per half hour. I also usually just tip the dealer in advance $5 for the half hour because I don't intend to tip on a hand for hand basis. On that setup, I think you need to be playing for at least $200 per person, and even that becomes a bit dubious if it takes a really long time to end it. The real HU specialists like to play for $5,000 each, but that's more than I can handle.