It's not about enjoying the loss. It's about enjoying the thrill due to the possibility of reverting the scenario, achieving a winning as consequence. Nobody likes losing, neither thinks it's fun, however, it's quite exciting to suddenly face a luck streak which bring profits back to you, after losing for a considerable length of time.

In most times, gamblers will just remain on the expectation, though, without being able to feel the pleasure of reverting a loss. And for them, it's already enough to continue gambling on long term. Since they can afford this hobby, I don't see problems at all.