It all boils down to societal shame. A lot of guys are working "real" jobs that they will lose or be harassed at if their work finds out. The same thing goes for women, which is why generally the guy lers are regular dudes with masks on and the gal lees are pro models. It is the pro model's job, so she is good or at least more good.
This goes into something else. I see complaints here like "why aren't there any clips of regular chicks." Weell the reason is what I said above, and we want to see their faces. We should be thankful for the pro models we got that can show their faces, the smiles we like so much.
I'm not a fan of masks on any one, which is 1 reason why I prefer f/f. But I understand the masks, no hate.