Right, be glad that you don't have to pay taxes on it as a barter arrangement. Luckily our system taxes earning money and sometimes spending money, but not saving money (at least not in the sense of economizing, there is that tax on earned interest for actual money in a savings account).

Of course, this is usually the problem for the single mothers on Welfare, they can't earn enough in a job to cover how much they'd have to spend to pay someone to take care of their child.