Consider the majority market of Facebook users, many don't know how to "hide posts" and will often be turned off whent their facebook wall begins to look like their hotmail account.
Don't always assume the average user has the know-how you do and don't always assume they're interested in solving the problem either.
And even if you know how it seems like every time I log into facebook (admittedly rarely) there's a handful of new spam games making the rounds. It's a little frustrating that there's no blanket option of block all of the stupid game spam, or switch from a blacklist to a whitelist. I'd much rather un-block specific games than have to block every game ever made.
