I remember hearing our marketing folks talking about enforcing MAP, at the company I used to work for. That company didn’t have the clout of Amazon, but we did sell premium kit.
For us, it wasn’t about money, as much as we didn’t want to ever be forced to reduce Quality; which included the shopping experience. We were concerned that outlets selling lower-priced kit, also had a worse shopping (and support) experience, which we believed (probably correctly) would reflect on us, and our most favored retailers.
Premium brands are often driven by factors other than just money. Brand reinforcement is a really big deal.
You're interested in Quality above all else, fine.
You're upset that you have competitors who don't care about Quality, fine.
So you make your website harder to use, so that... what?
I was just sharing my experience.
But it's not the manufacturers that do that. It's the cheap-slingers. It's their Web site that has the "click to reveal price" button.