Just make sure that the 1st time you open the game you willl have time. you have a week from the moment you buy it, that means that you will have a weekend to chose the moment you want the 24hs to start counting
i also feel that 24hs is a bit too much. but i guess they rather be generous and let some people cheat the system than having everyone else pissed of
i guess that if they make only 1 refund possible per purchase and you spend 50 bucks... buy a game, play it from start to end in less than 24hs, refund it to another one and keep that one ... it would be as if you "bought" 2 games at 50% each, but in the end EA got $50 bucks anyway
if they let you keep refunding ever and ever your $50 i dont see it as a very bright idea