Opinions about COA's at shows.

[Lordstan]

I agree that for the prices the public is paying the cert should be included, but the one thing that is missing in your calculations is that the promoter COA costs nothing for them to give out except a little in printing costs. PSA/JSA are separate companies that the promoters would have to pay to provide the service. That would cut into their profit or would mean that the autos would be $10 more.
The reality is that for those who need certs to buy autos, a show cert may not mean much. The TPAs are "independant" and have successfully marketed themselves as "The" authorities, so they can get away with charging more for their services. Right or wrong, there is a portion of the population that will only buy certed items.
Personally, I would never pay for certification of anything unless I was going to be selling it in the short term, especially if I just saw it autographed in front of me.