I hate to break it to you, but Madden, and sports games period, have a huge "RPG" element to them. Player progression and the stats that define who they are is Dungeons and Dragons on the grid iron.
Furthermore, nothing about an RPG lends itself to micro-transactions vs any other genre of games. In fact, I would say it is often less so when a game is online multiplayer because you simply piss off too many customers by catering so blatantly to a customer willing to put fourth actual money after their initial purchase or subscription fee in a game that promises and even playing field.
This is actually a big reason why people detest the EAS Ultimate Team System, because far too many players go out and buy super teams, and you get to face them with your team of standard cards.
I mean, it's bad enough to get beat by someone handidly because they're throwing bombs with Brady to Jerry Rice over some Dime DB, and picking off your 3rd round QB, but it's worse when you get beat by the same sort of team being controlled by some 12 year old who plays the game that can't even read a coverage, run lanes, play art, or understand personnel.