I almost walked off with someone else´s boots one morning in Astorga.
It was dark, I was trying to creep out without waking up everyone, the boots were identical to mine, but a size or two larger. I only realized something was wrong when I stepped down stairs in them, and realized they weren´t tight enough. I bent down to re-tie the laces, and woah. They were laced-up "wrongly." Thankfully I had not gone too far in them, I snuck them right back onto the rack and found my own pair, just where I had left them.
Close call. It can happen to you.
(and for the record, last year the Hungarian hospitalera at Calzadilla de la Cueza had her splendid German leather shoes "liberated" by a pilgrim. The person who was almost instantly caught, though: the Hospi just called ahead to the hospitaleros in Ledigos, Terradillos, etc. and described the shoes -- bright red Mary Jane flats. She had her shoes back within a day!)