There are many misconceptions here, some of which I’ve covered in the past. The primary one is that the draft exists as a mechanism to enhance competitive balance. Even a cursory look at how it came about puts the lie to that; baseball had lousy competitive balance for most of the 20th century, and no one in the game cared. It wasn’t until competition via signing bonuses became more of a key component in the acquisition of amateur players that the leagues got together and came up with a system for ending that competition. Any effects on competitive balance were secondary, and arguably unintended. The draft was, and still is, designed only to take away the rights of amateur players to have teams compete for their services.
Couple that with the extended rights that teams have to the players they draft, from six to 11 years, depending on how much time the player spends in the minors and how their major league career is shaped, something over which the player has little control. As a result of those two factors, the time from draft day to the signing deadline is the only time for perhaps a decade—and perhaps ever—that a player has any kind of negotiating leverage. Once he signs with a team, that team owns him until he accumulates six full seasons of major league service time. How can you possibly blame a person for wanting to maximize his return on the only negotiation in which he’ll have any leverage for at least six years, possibly an entire decade, and in many cases ever?
...
In 2004, Prior’s salary was $2.1 million, and while we didn’t know it then, his career was over. Even though Prior had been one of the very best pitchers in baseball in his first two seasons in the majors, he didn’t get paid like it, because the rules aren’t set up that way. You only get paid if you’re very good at the point where you can take your services to the open market. Do it before then, and you have no leverage. The various players who make the point that amateurs haven’t proven anything yet neglect to consider that even if the amateur plays well as a professional, there’s no guarantee at all of a big payday. They think you get paid for performance, and while that’s partially true, what you actually get paid for is being able to negotiate with multiple teams. Felix Hernandez is making $3.8 million this season; teammate Miguel Batista makes $9 million. You want to argue that performance is the determining factor in salaries?
...
So it doesn’t really matter what Ryan Zimmerman thinks. It doesn’t matter what your local columnist, making $63,000 a year without a fraction of the talent that Stephen Strasburg has, thinks. It doesn’t matter what talk-radio hosts, who have the same grasp of sports economics that I do of SQL, think. What matters is that the system is set up to deprive amateur players of any leverage, and when one stands up to that system and tries to make the best possible deal for himself, he shouldn’t be excoriated, or labeled as greedy, or derided as "unproven." He should be regarded as a man negotiating a contract, making the same choices we all make, taking the risks involved in going right up to a deadline without blinking. It’s his livelihood and his talent on the line, and no one gets to decide for him what "enough" is, not when there may never be any chance to get back to the table and ask for more.