Having paid exhorbitant fares on some flights, I wouldn't feel too badly about taking advantage of a hidden city ticket deal.
I'm not too concerned about the heads I win tails you lose contract of carriage, where even cancelled flights don't bring the traveler a refund of the fare paid for a service not delivered.
You're right, in that having given exposure to the practice will only encourage more travelers to look for and find hidden city deals, as long as they can travel with carry-on bags only.
Could this be the reason that many carriers now deliver gate checked bags only at the baggage claim at final ticketed destination?