Internet Junkies can get their SP fix by sweet-talking the Ahwahnee front desk staff out of the password to access the hotel's wireless network. They were very nice about it to us, we of the Uncultured & Unwashed Climbing Masses!
You do need bear cans for backcountry use.
You can get free WIFI (though it's come and go) in Curry Village in the open 'lounge' building in the hub of things without having to haggle (or 'happen' to overhear) a password somewhere. ;)
Backpackers camp is a resource for those within a day of a valid backcountry permits, though overstaying your welcome is enforced in peak season.
Yosemite Lodge cafeteria isn't a really a proper "cafeteria" anymore, and I'd tack on another $5 on curry's buffet.