I wish I could say that I wake up without an alarm clock, but that's not the case. If there would have been no concept of an alarm clock, then I would have probably woken up at my own leisurely time because I would have been unemployed.
I know quite a few people who don't need an alarm to wake up in the morning. My father is one such example. He will be up and ready at 6:30 in the morning. While I was staying with my parents, my mom would always wake me up. But now that I am too far away from my home, I have to rely on my alarm. It's not an alternative for mother's tenderly love, but at least you can snooze it for five minutes and wake up an hour late. :) Rest assured, to break myself from that habit, I usually set up at least 3 alarms every night!