well, we already have a "youtube knuckleheads" thread in the Media Center
Some people actually enjoy making
Have you performed any test to confirm your suspicions -- i.e., the Mitutoyo caliper is indeed much more accurate than the "hardware store caliper"
The videos put up by Rick and Salty do give a very good overview.
Anything more comprehensive would take a relatively concerted effort
Looks like a white balance issue. Photo may have been taken with a mix of natural and incandescent light. The vendor probably either did not look closely
Wow, you really need to take some finger stones and polish up those calipers. And the measuring tips look like they have overgrinds. Hopefully those