I don't see how they would be considered "unfair competition" under any meaningful definition of "unfair competition" (ie. something that isn't just "bad for consumers"). It costs nothing to sign up for loyalty programs, and being in a loyalty program doesn't hinder your ability to comparison shop or go to the store with the best deals. Yes, it does require you to jump through hoops to get the best price and is effectively price discrimination, but I don't see how it's any different than other forms of price discrimination (eg. having rotating specials so you're forced to plan ahead and/or stock up).
It would probably be a stretch and overreach, but the angle I would take is that they are competing not on the merit of their products.
Consider airline miles. Each time I purchase a ticket, instead of choosing the best deal (fair competition), I am incentivized to choose an airline I have chosen in the past so as not to fragment my points across several accounts. And of course, these "rewards" are all a price passed on to the consumer.
I have been buying flights for 20 years and not once has that crossed my mind.
It goes:
Number of stops -> arrival/departure time -> layover time -> cost.
I also feel like I only ever have 1 nonstop flight option, maybe 2. Maybe the biggest airports have sufficiently redundant flights, but even then, surely most people know points are worth 1% at most, and in my experience, flight prices differ by hundreds.
I would be confused if I learned people were buying flights based on points/miles. I assume the miles/points are mainly utilized by very frequent travelers, or people using credit card rewards.
