Is this unethical?

[X-Calibre]

I was at a 6 max stars table the other day and one player kept buying over and over at the table with the min buy-in. He was bad, so obviously i wanted him at the table. However his strategy of always min buying cost me some money for sure. After many orbits it was clear what he was doing. When ever he would get somewhat short stacked, down to his last few bets, he would wait till he flopped a drawing hand and then raise once or twice to get all his money in before the turn with everyone else calling along. Once the hand ended he'd either keep playing with his winnings or immediately rebuy for the min.

It was obvious he would change his play when down to the felt. He would make irrational raises and reraises in multiway pots whenever he was short stacked. He would get 1 to 2-3 on his money then on the turn when the flush misses i would bet (if my hand was good) others would fold and i couldn't charge him to see the next card because he'd already be all in. Essentially, he was able to eliminate reverse implied odds on his drawing hands.