It is clear that if enough people use this method, prices published for a two part flight will stop being cheaper than prices published for one part of that flight. It isn't clear one way or another (at least to me) whether or not the overall consequences would be worse.

A more common example of the same thing: it is frequently the case that a round trip ticket is cheaper than a one-way ticket, and for this reason it is not uncommon for people to buy a round trip ticket and only use the first half. If people did this frequently enough, you would no longer see round trip tickets that are cheaper than one-way tickets. It is not obvious at all that things would be overall worse for people, rather than better.