What? I have not heard of a babysitter agree to babysit without also agreeing on a price beforehand. Where does this happen?

I definitely would not trust my kids with someone willing to accept that deal.

No? The price for babysitting is always agreed up front. At least, I never seen anyone babysit or have babysitter without price being clear.

> Babysitting.

Not generally.

> Obviously, you don't decide if you're going to pay for restaurant service; you decide only whether you're going to hold up your end of a cost sharing deal.

Tipping is not a “deal” that you have committed to, by definition.