alt Hacker NewsStores already have that in the form of having cheaper and more expensive products in the same category (for example, 5 different brands of tomato sauce).
The practice that needs to be outlawed is invisible and per customer pricing. It would be the airline for the same class of seat charging different amounts because, for example, their profile of the flier shows they recently searched for "casket" and so they are likely heading to a family funeral.
It would be as if the airline for their economy class offered the flight for $1000 if you don't play, $600 to attract customers into buying, and $800 if they find their customer is desperate. All for the same seat.
They already do charge different prices for the same seat, based on their assessment of the type of passenger you are.
You've picked an "evil" example, but what price discrimination really tends to look like is charging richer people more.
Prices are generally lowered for poor people because they'd rather have your $300 than have an empty seat. If you don't have $800, no amount of desperation will make you pay it - you'll just miss the funeral.