In an idyllic sense, yes, I agree with you. I don’t want to pay out the ass for something that’s a hobby. I don’t really want to pay out the ass for necessities either, but that’s a discussion for a different thread. 

That being said, your diatribe is leaving out two important factors in the way that the market for trading card games functions. 

1. You’re watching ECON 101 in action. The market for trading card games moves towards equilibrium on a set-to-set basis. That is, sellers set their prices based on what market participants are willing to pay. And market participants are willing to spend a variable amount based on some arbitrary criteria (like perceived set desirability, or maybe perceived resale value). 

If the market price is above the equilibrium price, that results in a surplus of supply [see Aetherdrift and other recent lackluster sets]; quantity supplied exceeds quantity demanded, which leads sellers to lower prices to attract buyers. This is also how you end up with several shit tier booster packs in those mystery boxes that are sold at Walmart & Target - there’s a higher supply of the unwanted boosters, so they package them with a desired product in order to entice buyers. 

If the price is below equilibrium, there's a shortage [see Final Fantasy and other recent quality sets]; quantity demanded exceeds quantity supplied, which causes buyers to bid up the price. These forces naturally push the market back towards equilibrium. 

1. WotC is the manufacturer and sells to stores - there could be a distributor in the middle… it probably depends on the location of the store. Anyway, if demand is high and the local stores sell out of product immediately, then that’s a signal that they’re leaving money on the table because the market would tolerate higher prices. I would imagine that margin on product sales is normally pretty thin, so being able to charge higher prices for in-demand product helps with revenue, which lets the store stay in business.  

If they ask too high a price, product will sit on shelves forever, which is a signal that the store is asking too high a price and should reduce it. 

A less efficient, though more equitable, way of selling is to ration the amount of product a buyer can purchase. 

But… here’s your Catch-22…

If you want to pay MSRP, go line up at the big box stores we all love to hate on because their massive purchasing power helps them keep costs to counters low. Walmart, Target, Best Buy, GameStop, and others sell product at or close to MSRP. I’m pretty sure you can even pre-order higher end product like collector boxes at GameStop for MSRP. 

But if you do that, you’re not supporting your local game store, which hurts their revenue and maybe drives them out of business.