To maximise profit, a corporation must find the highest possible price that customers are still willing to pay. If a company finds a way to do this separately for each customer, then the other market players need to follow, otherwise they will loose their capital (i.e. shareholders jump ship). Information asymmetry is a very devious market hazard, it makes it such that the market appeara to be working perfectly well, but from the consumer point of view it appears like fraud. Nothing you can do other than protecting your data.

Companies sell at lower prices than the maximum acceptable price of the customer all the time for a variety of reasons. In order for what you say to be true there has to be a monopoly - otherwise competition will drive prices below that point (and this happens all the time)

There doesn't have to be an absolute monopoly, just a monopoly to a very specific service that you are looking for. Like a direct flight on a less frequented route. Or a delivery of baby wipes that arrives until tomorrow lunchtime at your home address. Oh, you also searched for "what to do when out of baby wipes"? Better jack up that price then...

Because of companies like Amazon. Most specialized shops in many countries have died because they can't compete with Amazon's leverage and scale, and it will only get worse.

This already happens and has been going on for a decade. https://www.theguardian.com/money/blog/2010/aug/07/computer-...

Monopolistic behavior. Lots of products can only be bought from a couple of companies. Competition need not apply.

Even in a competitive market place they can collectively decide to overcharge the same customers.