[otterley]

The declaration of intent is made before the stopover city is revealed to the prospective buyer. You don’t get to specify a stopover city when you select your origin and destination; only after those are entered is the routing revealed to the customer.

[p49k]

I hope you can take a step back and see the absurdity of your argument. Using a search engine in one particular way doesn’t imply intent, nor does buying something that’s not exactly what you need.

Airlines can’t have it both ways: if they wanted to, they could make customers pony up a “trajectory abandonment” deposit, or force customers through an interstitial in which they explicitly agree to extra charges, or something similar, but they want the financial/competitive advantage that comes with the customer not having any worries (i.e. being clueless) about being charged for missing or not taking a connection.

[otterley]

We’re talking about a situation in which the customer already knows they want to go to city B. If they’re being truthful up front, city B is the destination they’ll be putting in the destination box when searching for tickets, and they will get a routing to that destination without any additional segments when they do so (assuming, of course, that the route is possible).

[kryogen1c]

Your argument seems absurd to me. The price break exists because it's a good deal for airline and long distance flier. Abusing this system only ends in two ways: airlines punish short-stoppers, or raise prices on everyone.