Can a shop use your opinions for its customers?
In short: Yes. A shop can show a customer the opinion sheet for a card, with its method and photographs. The sheet is an opinion, not a guarantee, and it says so.
Shops use opinions to put a documented method behind higher-value singles. The customer sees the checks and the photographs, not just the shop's word.
For cards pulled from sealed product, a documented break goes further: the card carries the video of its own pull. I never buy or sell the cards either way.