This could be SO easily circumvented. Just open an office in another location (a subsidary, perhaps) and have it do the hiring at the prevailing wages at that location.
This is not so easily circumvented. If an employee on H-1B transfers to another location, the employer is required to file an amendment to the H-1B petition and go through the prevailing wage determination again. From USCIS website [1]:
You must file an amended H-1B petition if your H-1B
employee changed or is going to change his or her place of
employment to a worksite location outside of the
metropolitan statistical area (MSA) or an “area of intended
employment” (as defined at 20 CFR 655.715) covered by the
existing approved H-1B petition
