Except where it doesn't work, such as in the restaurant business, where some non-trivial percentage of the supply is superfluous and will go out of business. Of

Except where it doesn't work, such as in the restaurant business, where some non-trivial percentage of the supply is superfluous and will go out of business. Of course, they will be replaced, so there is an argument that it is at least stable, even despite the high turnover - perhaps that's what you're meaning?