Sorry if this is old news, but I haven't seen it posted around here...
Grand Theft Auto V's multiplayer mode--GTA Online--could introduce microtransactions, if a new claim turns out to be true. Reddit user 1880 discovered a file from the store section of the GTAV menu (which is currently empty) that mentions something called "Cash Cards."
This XML file mentions downloadable content from the game's special editions, as well as four "Cash Cards" ranging from $100,000 to $1,250,000.
"Cash is king in this town. Solve your money problems and help get what you want across Los Santos and Blaine County with the purchase of cash packs for Grand Theft Auto Online," reads a description of the cards. "All purchased cash is automatically deposited into your character’s bank account. Spend wisely, cash therapy is fleeting."