I did an overnight tour this past weekend. Had to stop half way for some last minute grocery items. Left the bike outside the store, which is located in a very busy shopping center. Later, I stopped and aet lunch by a creek. My back was turned the entire time. Camped that night at a very busy state park. Left the bike leaning against my picnic table and all my gear outside the tent. The next morning I took a snack break by the same creek on my way home. Back again turned. Later made a stop at a busy c-store across the road from the aforementioned busy shopping center. Left the bike outside while I did so. Then I stopped by my local club's spring picnic in the city. Leaned my bike against a wall (like dozens of other people did) and forgot about it. Last stop was my local bar. Again, I leaned the bike against a wall. I was mostly outside, but I did go inside twice to order pints.

Never locked the bike once, yet it (and my gear) did not get stolen.