Ultra low-cost airlines are pretty aggressive in upselling seat / baggage / food / fare class upgrades during the checkout process. It is annoying to have no idea what a ticket will really end up costing when it pops up in Google Flights or whatever, but I don't think that's enough to call it a dark pattern since everything is clearly disclosed before you pay for anything. Airlines are very upfront about all the things you aren't getting with your ticket.
Ultra low-cost airlines are pretty aggressive in upselling seat / baggage / food / fare class upgrades during the checkout process. It is annoying to have no idea what a ticket will really end up costing when it pops up in Google Flights or whatever, but I don't think that's enough to call it a dark pattern since everything is clearly disclosed before you pay for anything. Airlines are very upfront about all the things you aren't getting with your ticket.