The unfortunate reality is that it's really difficult for the employees themselves to make sure that everyone is being paid equitably in a situation like that.

The unfortunate reality is that it's really difficult for the employees themselves to make sure that everyone is being paid equitably in a situation like that. At least with (reasonably sized) salary ranges, people will have a general feel of where they are - and then it's also easier to do other analysis, e.g. "does the company, for some reason, only ever promote men?"