There are no fixed wholesale prices for ammo today.
There is MSRP and suggested DLR but distributors set there own mark-up on what they sell it to dealers for.
It boils down to supply & demand. Basically, there is no supply and there is a tremendous demand....why doesn't matter .
Big Box Stores may be on a direct drop ship program and annual buy in...line Cabela's, Walmart, Dick's Sporting Goods. They are getting orders filled at the "old" price and pay no freight. FFL Dealers usually have to pay UPS/Feded Ground freight on small lots which adds to the price. A retail location with brick/mortar and utilities...has to make a profit.....or go out of business.
Wallyworld and Academy are selling ammo well below what dealers would pay to buy the same stuff IF available today.
Nobody is getting rich off ammo sales. IF somebody has what you need IN-STOCK...the price is the price. Ammo may go back down SOME in about 18 months...but don't count on it.
US Manufacturers are at 100% of capacity now. There is NO late date ammo being sold as Surplus by Foreign Governments due to UN adopted regulations.
In today's world...when you come across ammo, bullets, powder or primers...buy them !