Unless their policies have changed in practice, I am not sure that it means what you think it does. One might consider testing it in practice. And specifically the Pi Hut policy...the stated reason is bogus. The reason *isn't* shortage of supply and hasn't been for pretty much the last year.
One doesn't have to be Sherlock Holmes to see who's sticking to the "One per customer" rule and who isn't when those who don't are publicly stating they don't.
You can only tell where the stated policy is "one per order". There is no way to tell if the companies saying "one per customer" really mean what the RPF has said or whether their actual practice is "one per order".
It doesn't look good for the Foundation if they have retailers who simply won't play by the Foundation's rules. If I had official retailers refusing to play by my rules I'd be telling them I'll be looking for alternative retailers who would. Such a threat would normally be enough to slap a professional business back into line, and good riddance if they won't play by the rules; they wouldn't be the sort of people I'd want to do business with.
I think a rather more critical issue here is if the Foundation is attempting to impose a rule that they have no way to enforce. I can think of two better approaches right off... One would be restate the rule as "this is what we would like (but can't enforce)" or if the Foundation arranged with the retailers to only sell a Pi0/Pi0W at the discounted price with a coupon, and the coupons would only be available from the RPF. Accompanying a coupon arrangement it would be a very good idea to announce a "regular price", that is a non-coupon price. Granted this wouldn't have worked out of the gate when there was a genuine shortage.
Note also that there were posts right from the beginning of people buying multiple copies of the MagPi with the Pi0 attached...and nothing was said about it. The whole "one per person" really looks like a post hoc
effort to contain demand after it was realized that people really did want multiple Pi0/Pi0W boards and were willing to do whatever it took to get them. In part, the RPF has been a victim of its own success.