I'm not sure how that's fair. Should they also adjust your salary based on how expensive your car is? The value you provide to them remains constant despite where you choose to live. Why should you be punished for living somewhere less desirable? Presumably part of the reason you would choose to live in a less expensive location is so you can save more money. This to me seems like they're pocketing money that should rightfully be the employees.
I like the transparency in theory. In practice I don't want my salary to be so easily determined by a quick web search. It could really inhibit my ability to negotiate a higher salary at my next job where they'll likely offer something like 5% higher than my current job. It's hard to justify a 50% pay increase.
I doubt most employers would hide that they're paying you less due to where you live. Instead I think most would bring it up in negotiations hoping to use it as a means of keeping your salary low. And honestly, the argument that your salary should be adjusted based on cost of living would work on a lot of employees even though it shouldn't.
"I'm not sure how that's fair. Should they also adjust your salary based on how expensive your car is? The value you provide to them remains constant despite where you choose to live. Why should you be punished for living somewhere less desirable?"