That’s just bad accountants. CR sells a book through WotC’s publisher. That’s bank. CR is sponsored by D&D Beyond. THEY USE IT ON THE SHOW. That’s subscriptions. Every book or miniature that people buy because they were inspired to want to play is money Hasbro earns off of their success. It’s all advertising.

Promo codes usually give money to the person shilling the code as a fraction of the promo derived sales. If the company is paying you for advertising, like on YouTube channels, that’s how it’s usually done. But people with established advertising channels can run that the other direction: we’ll promote your stuff and you give us 5% of the gross.

I think WotC could be promoting Dwarven Forge without cannibalizing their own sales, for instance. They make different kinds of miniatures.