probably isn't his real e-mail. Most likely several people have acces to this adress. I suspect they filter the mail for Steve. And answer some of the mail on his behalf.
Can you imagine steve reading thousands of mails every day, answering some of them, and have to search for his real import mails from apple.
It is, trust me.
He has an executive staff that sort through and read his e-mails. I had an issue once, wrote to his e-mail and one of his "Assistant to the Executive" folks got in touch with me to resolve the issue.
But please, try and resolve the issue through store means with a store manager or higher up on the phone first if you can. The more this e-mail gets abused, the less likely people who really need a hand will get it.
sjobs@apple.com
I've heard you need to kindly point out the terrible experience you had, and that tends to get you places. Be firm, but not rude.