He must have thought of it, how is every company wanting to hold bitcoin and he has the opportunity to do same using his salary, maybe he thought this way and decided to use bitcoin to receive his salary to keep stacking up bitcoin. With this he wouldn't be finding it hard to accumulate as he will just be holding his salary instead, with this good move I don't think he would even be thinking of selling now as he must want to be in profit with his salary, it's the best move any CEO could do, must of the well known companies buying bitcoin don't really want bitcoin but as for the company it will help generate more money in future that's the only reason they are there.