@madison --
I'm a manufacturer who sells at retail and at wholesale.
My wholesale customers are those who are buying products in order to resell to others. I wholesale to gift shops, arts and craft galleries, department stores, apple orchards, Christmas tree farms, etc. The margin between my wholesale cost and the prices at which they sell my products at retail is the money that pays to run their business -- salaries, rent, utilities, insurance, etc. and hopefully a little profit. My retail customers are people who buy my products and services for their own private use. Just regular private people who want to decorate their home, buy gifts, and the like.
So ... if you were a retail customer of mine, but thought you could find a way to buy my products at wholesale pricing, wouldn't you try? Even if your answer is "no," I guarantee many others would answer "yes" in a heartbeat. These "essentially retail" customers are ones who want to "game" the system.
One way to discourage the gamers is to set the minimum order cost and/or the minimum order quantity high enough so the typical retail customer has no incentive to buy. That's what I was talking about in my first post. Most people don't want to buy 6 of something in order to get one or two for their house decor.
Another way is to require the customer to provide a state sales tax ID or business ID, which one should do anyway so you can document you are a legitimate wholesale supplier and are selling to legit retailers. States want to collect their sales tax and income tax, and if they aren't getting their tax income from you, they want to know who they should collect it from.