I think Rabbits' that you and lots of others have to accept that some shooters will spend more money on accesories such as mounts for two or maybe three main reasons.
First up is the obvious one and it's because they simply have the means so they can and they do;
Second is that they have an eye for quality engineering and design with my personal caveat that, maybe, the reasons behind the design are possibly flawed and baseless in the real world;
Third, I would say, that it imparts a certain degree of confidence in the rifle/scope/mount combination leaving the shooter free to concentrate on his/her contribution to the shot.
May I add a fourth: Peer pressure or a close relative. A person may be continuously told by others that something is better or keeps reading that it is better so begins to doubt his/her equipment to the point of deciding 'I must have that, it will improve my shooting'. So a change is made even though it may not have been necessary. But, and it is an important 'but', point three above can then kick in ....
Cheers, Phil