I'd doubt rather seriously that anyone would disagree with that - of course, that's a big part of the way you accumulate enough money to afford to buy a professional sports franchise too.
Don't forget - none of what I mentioned above begins to address the money MLB/owners have agreed to pay minor leaguers and prospects while they're not playing either. It's not nearly in the same stratosphere, but eventually all the money going out with none coming in takes a toll - the folks that own your local watering hole aren't paying bartenders to fetch you a beer when you're not allowed to hang out at the bar (nor can they afford to).