That's such a ridiculous setup. What if you were buying a gift for your child? You must bring your daughter with you to buy her present and ruin the surprise.
Not entirely.
If the product is a limited supply intended for children, it can make sense to require a kid.
Both as a business strategy to bring kids in the store(where they might find other stuff they want).
As well as a counter to people who would just buy out the stock(scalpers and/or otaku-in-20s/30s).
The surprise isn't ruined, just a different form. Surprise the daughter by unexpected detour to the toy store, where you also surprise them with the rare thing. Honestly kid me might be more excited to be taken to toy store and then watching as my parent buys something I really wanted, than I might unwrapping it as a gift on birthday or a holliday.(of course it wouldn't have the same effect if I routinely were taken to a toy store though)
I don't disagree with your point though. Unless the item is just that exclusive, even with other considerations, at bare minimum it would make sense to at least compromise and allow a family photo as an alternative. Otherwise the store is literally risking losing a sale and possibly a customer(who may find that inconvenience not worth it and go to a nearby competitor)
Either way this is hilarious that an adult man with the form of a little girl is bypassing the stores intent and buying a gift meant for little girls as a gift for another adult man.