The phrase "to exploit a loophole" means taking advantage of a technicality or a gap in the rules or laws to gain an unfair advantage or benefit. Full definition
In addition to mistake fares, there are often big opportunities to earn miles by exploiting a loophole in an incentive structure. (chrisguillebeau.com)
Every household's life situation, values, health, and culture play a role in deciding which route to take — or if its even worth exploiting the loophole while its open. (businessinsider.com)
He only taught for one day as a substitute teacher in order to exploit a loophole in state law. (teacherpensions.org)