I agree - my provider charges a daily rate as well. I think our rate is $35/day.
I'm of a different mindset, however, as I believe in the quality advantage that my provider gives to us. I don't believe in paying our child's care taker less per hour than what minimum wage workers are paid. I cannot, for the life of me, think of a more important expenditure in my life at present than my child's care when I'm away at work. If I have to pay a bit more for quality care, so be it.
I have been upfront with my mindset on this with my provider and have told her that if she ever feels that she needs more money to provide that level of care for our daughter, to just ask. I'd much rather that she be satisfied with her compensation than dissatisfied and have my daughter pay the price (through the lack of educational toys or equipment, or having to take second stage to larger numbers of children, etc). This is not to say that we may not consider other options for child care if we feel that we're being taken advantage of, but that's our right as clients as well.
My husband and I viewed child care as one of the necessary thing that played into our preparation prior to becoming parents and something that we just didn't want to skimp on. Again, it's one of the most important things we pay for as we see it as a very important extension of her overall growth, development and education. Had we felt that we couldn't adequately provide for her, we would have waited to have a child.