Games you won't sell is one thing, but what about games you find you don't like? I sold Fifa within a couple days of getting it, because although it's a decent enough port, I didn't feel it translated especially well to a handheld. That's a game I'd be stuck with if I bought digital.
There are benefits to going digital, as I said I'm happy enough with Steam, but for the time being the pricing structure outweighs the benefits. With Steam you know if it releases at a price above what you think it's worth, it won't be too long before it hits a price you're ok with paying. When that happens with console game as well I'll probably be more inclined by digital copies of games.
Fifas pretty damn good on the Vita...... You wanna try the 3ds version, now THAT sucked.