Most hotel laundry services I've encountered seem to be priced for one or two critical items. Cleaning a week's worth of items would be prohibitively expensive for most people, and I would be surprised if big productions would be interested in burning several hundred, if not thousands of dollars a week per person just for laundry.
On the flip side, it would be rather amusing to see the entire support cast for Madonna or U2 huddled about grumpily in a coin laundry waiting for other people to finish.