Among other things, free market theories assume that the employee or the consumer has perfect knowledge, even if “unfortunately” s.he doesn’t, let’s help them then.

The salaries of each employee, with their bonuses, are already known, as well as their categories.
If it’s displayed on a website then every employee of that category could know where to go in order to get a better pay(, yeah, i don’t believe it solves the most important problems(, e.g., monopolies, surplus value, lack of democracy in the workplace, …), but it wouldn’t be worse than nowadays).
If the consultation of this website is insufficient, and it will, then an annual text summarizing the result of such research for them should be sent.

Similarly, for each product sold, a little screen underneath should indicate where’s the cheapest same product ~50kms around.

I’m sure they would be glad to realize that they can put into practice their theories(, unironically for the honest ones though).