I was thinking of this as well (as a way to work around the fact that, for example, it might make more sense to slap two aircraft on alternating rotas than to "force" them back to base due to scheduling) but wasn't quite sure how to phrase it.
For example, if I have (for example) LAX and JFK as bases, a flight LAX-Cleveland (which is timed to take advantage of a lull in airport business) might be better served by carrying onwards to JFK (arriving before 2300) and overnighting there than returning to LAX and showing up at an awkward hour or having to overnight in Cleveland. This would also allow for a bit of structural flexibility in long-haul rotas...again, it might make more sense due to timing to send a TATL/TPAC flight "back" somewhere (and then in reverse). At major airports, "kludge a flight in where a slot is available" does become an issue.