"My gf is a waitress and in school, and if someone tipped her in bitcoins i would be furious, she has no way to use that."
The fact that they can't easily spend it is an advantage imo. Also, one of them is studying economics. If the price/value does keep rising, they'll be really happy. I offered to take back the coins anytime in exchange for USD. I advised them to read up about it and hang a "we accept bitcoins as tips" sign. I also made sure to tell them this thing could crash and burn. I think I was being fairly responsible but it's probably risky sending bitcoins to anyone after a few beers.
Common , lets not see advantages in every aspect of bitcoin.
Most waitress work for the minimum wage and they badly need those money that they receive as tips.
And now , you are asking those guys and girls to wait till they get around 100$ in tips then search for somebody on localbitcoins that is willing to exchange them , at a rate that is obvious much lower..
BAD IDEA.
If you want to tip them in mbtc , send them as an extra tip.
Don't force people to embrace your ideas. That's not what bitcoin was suppose to be.