I guess I'm confused. Is your issue that your supplier publishes a catalog with prices in it or that you think those prices are what they sell to the general public at?
When I look up an item in the catalogs I have, I know I am looking at what I will be paying as a
sign manufacturer. It is already "discounted" and it is assumed that if an end user got hold of the catalog that ...
- They wouldn't be in the market for what is shown there.
- They would have to register with and be approved as an authorized customer by my supplier.
While opinions may vary on who such a vendor should deal with, my policy is that if I become aware that they are selling to the general public, then I will either reduce them to the lowest tier on my approved vendor list (only buying from them what I must have and cannot get elsewhere) or remove them from consideration completely.
It used to be that a supplier would publish a catalog without prices and then supply a separate price list. That allowed
sign shops to show items without providing their cost to their customers. With the growth of the internet, anyone can easily determine your costs, so you have to ignore those that try to beat you up with it and focus on the fact that you're providing much more than raw materials.
Suppliers like those you named do provide you with prices on products that are intended to be part of something greater. You can call them wholesale or distributor or dealer or jobber prices. The prices they pay are based on their ordering volume. The prices they charge you, which are often negotiable depending on your volume, are for you to acquire them for your needs as a jobber/manufacturer. If your customer wants to try to qualify him or herself to buy from the supplier and is willing to accept the quantity needed to order, then that isn't your concern any more than if he or she went to an art supply store or Office Depot and found the same or similar items. Or consider that one can buy a case of
paper at Office Depot for a half a cent a sheet. That doesn't mean that my printer is going to print finished work for me at that price.