this is non sense. they can sell their products for whatever amount they want. the only restriction would be on an "advertised" price.
btw.....i feel your pain on costs. up here in canada we deal with this BS all the time on many different products. when it comes to scuba gear in particular, it depends on the brand. some brands are very good at setting prices that are fair while others can be half the cost or less across the border in the u.s.
Canadian divers have it a lot easier as they can just waltz across the border - when it’s open.