Here in Japan maybe 95% of bikes use them, but we don't have the theft problems you guys have. They are basically useless because the bike can be tilted onto the front wheel and wheeled off. So many people loose there locks here and it's too common to see people wheeling their bikes home. I'd doubt anyone there in the States would blink an eyelid if they saw someone wheeling a bike down the street as they'd assume the same as us...the person lost their lock.

The only they are good for, is to stop drunks from riding your bike home because they don't have taxi money.

Get a decent lock and lock the bike to something.