Maybe he though he was making good money and found out what others are making.
I have told this before. Could you imagine LeBron finding out he was just the third highest paid player on his team, while having been told by his coach that he was the highest paid player in the league? That happened to Gordie Howe in the 1960s. Gordie was naive, of course, but it could only happen because NHL salaries weren't divulged. The owners wanted it that way because it keeps salaries low.
Screw the union. Make pay public. The NBA, NFL, NHL, Major League baseball, actors, etc. all have their pay public because it benefits them. Mario Lemieux had a contract that gave him a million dollar more than whatever Wayne Gretzky was getting, ffs. It's the same with everything. From houses to art. Everybody gets it except MMA fighters.