Now that you mention the auditing etc, a lottery system would probably be an easy way to get people to literally buy into an online ID scheme, not because it would necessarily be privacy-preserving, which would depend on implementation details, but because a not insignificant number of folks seem to like the chance to win money. Considering many states already have lottery systems, the ID code tickets could probably be provided alongside lottery tickets for free or nearly free, and employees already have the training to check/scan IDs. If there was an incentive such as the possibility to get discounts, win prizes, or tie-in purchases of some kind, I think it could work.
Many stores that sell lottery tickets also sell gift cards, so that technology could also be used instead or in addition to ID tokens at the point of sale. There are a lot of sponsorship opportunities available for cross-promotion.
“Please drink a verification can” was probably more prescient than was at first apparent. Mike Judge saw this whole thing coming from a mile away.