A thesis is more a proof that you can handle a particular type of research or investigation. I myself haven't touched the particular specialised field of my thesis since I submitted it.
It also doesn't mean that the Author particularly enjoys or finds the topic that interesting. I've often heard that if you have a favourite topic, you should at best find a thesis topic that is adjacent or related, and I'd tend to agree.
There is nothing saying that a product needs to pay for all the processes inherent in making that particular product.
There is value in having flat pricing across all your products. Especially if some of them aren't as popular, yet might driving purchasing decisions.
Consider cafes that need to stock decaf, but want to buy from a single supplier. If you don't have decaf you're not going to see their custom, despite their order largely being non-decaf.
So they'll want to supply decaf, but in order to encourage the sale of it (so they can reach a better economy of scale) keep the price the same as the equivalent non-decaf.
It's not greed that has varied. It was an inflationary shock. Greed explains why it hasn't gone back down once the shocks are gone. It's basically price collusion - nobody wants to be the first to decrease prices, so nobody does.
Before the inflation, there wasn't an opportunity to collude in this manner.
Which is a bit sad. My thesis is available online. Which might be sadder.