You said "charging two people for the same route differently" is bad: airlines do that constantly and that's why there's dozens of fare changes, fare buckets, sales, codeshares, etc.

Regardless, the bigger point is that businesses already have a ton of levers to move for pricing: sales, loyalty programs, and regular price adjustments. None of those are considered discrimination. Why does the buyer's home address fall into this protected class; particularly for any service that involves transport, delivery, etc to that address? There's a clear relevancy of the address to the cost of a service based around that location.

I suppose you are misunderstanding me on purpose, but let me try again in very clear terms anyway: Offering the same service or product (a specific flight if you will, a chunk of butter of the same brand in the same store at the same time) to two independent customers at different prices based on prior knowledge about them unrelated to the specific good or service is fundamentally unjust.

They meant something more specific by "route".

> sales, loyalty programs, and regular price adjustments. None of those are considered discrimination. Why does the buyer's home address fall into

Because everything you listed applies to everyone equally! Assuming a normal loyalty program anyone can join.

> any service that involves transport, delivery, etc to that address

Shopping at a grocery store doesn't involve that. But sure most forms of charging for transport based on destination are fine. That's different from charging two people differently to go the same place at the same time. "Home address" is just an easy piece of personal info to mention.

(An exception to that most would be like the hospital example, charging more for that specific location inside the general area because the buyer seems desperate.)