They have option to sell at higher market price though. This is not really a problem, I wonder how the creator of bitcoin really planned about this system which definitely lead us to concluding that the market price of bitcoin will soon increase way up higher if we all take the halving positively. Or else, miners will be demotivated and leave everything they've started behind. I just wonder about one thing. If all bitcoins have all mined up, who will process the future transactions? Miners will don't have anything to get from the system.