My usual practice is to never let my bike out of my sight, so I don't carry a lock. My training rides take me out to sub- ex-urbia in about one hour from the city when I might first would have to go to the bathroom. I have had no problems bringing my bike into a fast food place, and doing a quick visit...I don't even wash my hands.

My thought is that I'm out where car is king and most of the other patrons have driven there and would have to put the bike in their vehicle to flee. Being in suburbia where cars reign, I'm also somewhat of a spectacle when I clack-clack-clack through the place and a thief would be more conspicuous to the other patrons. My other option would be to find a secluded spot to go, but there are tales of guys being arrested as Level 3 sex offenders, and i have to be really way out in the country to find those opportunities.

Nonetheless, this thread is making me nervous, and I had bought a lightweight cable lock last year that I think I'll use this season for those brief pit stops.