In some cases I do think there is a limited talent pool. Unwillingness to negotiate in those cases usually means the company would rather simply suffer along with worse business outcomes, or try to invest in a totally different area of work, than to accept they are at a negotiating disadvantage and that it may be the case that painful company culture changes have to be made (like giving some people private offices and not others).

“The market can stay irrational longer than you can stay solvent,” seems apt for this.