I understand your concern on the matter but you have to take note that suppliers normally don't post their reseller's price list for everyone to see. Prices posted on their websites are actually retail prices for end-users. If you wish to sell their items, you will have to join their reseller's program to view their special rates.
When it comes to profits, bear in mind that wholesale pricing usually works in volume buying. They have a set price structure in place so ideally you allow greater profits if you purchase 50 units compared to just 5 units.
Hope this clarifies.