Yes, you lucked out. If the thief had had ten seconds to build up enough speed to outrun you, you'd be dependent on the kindness of strangers in a car to help catch him, and around here, most drivers would ignore you. Even if you are watching the bike from inside a business, it's likely they can outrun you by the time you get outside, and all you can do is wave good-bye.

If you really don't want to lock the bike for a minute, at least drop the chain off the chainrings, or put it into the highest or granny gear, which ought to slow them down for a few critical seconds. Or put a toe strap through the front wheel to the downtube. Though around here, someone would then just pull up in a truck and throw your bike and gear in the back, and be gone in less than five seconds...You must tour in nice areas!