MLB has never made a rule about it, so you're basically complaining about a non-issue.
If the market supports the team, that is all that matters, and obviously, the market supports the Yankees. As a fan, I'd be pissed off if they didn't spend the money we gave them to improve the team.
All I hear is complaints from other teams' fans, but then I watch games during the regular season and stadiums are less than half full. The Rays, while in first place in one of their best seasons, had to give away 20k tickets to a game during the pennant race this year, and only had 37k total at the game! That is embarrassing!
Yankees Stadium hits 95% every game... EVERY SINGLE GAME.
Texas deserved to beat us because the Yanks played like they didn't want it, and I have no problem saying that. But whenever you guys knock on the Yankees, just know that real Yankees fans smile because the jealousy is what carries us through non-championship off-seasons.