It's not about "good enough." It's about being compensated fairly for the value you provide to your employer. Baseball players wouldn't earn nearly the money they do if they weren't generating literal billions for owners.
Say you're on a sales team for a software company. You've got, I don't know, 13 sales guys and 12 software developers. Your product, through new innovations and developments, generates several hundred million dollars in new revenue for your company. That revenue literally wouldn't have happened if you and your co-workers weren't in the office every day. But your company pockets the revenues and the profits, and gives you a marginal raise that doesn't even carry with the rate of inflation (MLB's luxury tax threshold increases over the next few years are about half the rate of inflation).
I doubt you'd say, "Thank you sir for this generous gift! I greatly appreciate you! Thank you for allowing me to have a job!"
Edit: And don't talk to me about "us working stiffs." For much of the past three years I've been freelance, working hourly. In some roles I've earned eight bucks an hour, in one I earned $50 an hour but that was a contract gig that lasted less than two months. During my career I've been in ownership, I've been in management and I've been in rank-and-file, and the vast majority of that career has been in rank-and-file. At the rate I'm billing right now for a particular client, it would take me 520 years or so of full-time work to make a single year of Yu Darvish's salary. And you know what? I don't fucking care, because I know the incremental value of my work for my client's bottom line isn't even in the same ZIP code, not even the same state, to what Darvish's is to the Cubs.
Again, I don't sit here and think, "Bah, greedy ballplayer, he gets paid more than enough, boo hoo." I'm much more concerned with a rising tide lifting all boats.