Every port we've been in, including Barcelona, has warned of Gypsies and pick-pockets. I carry my stuff in my hip pouch worn on my left hip, easily within my reach and view. In Barcelona when we we were riding the subway I had a most weird encounter with a young couple--a guy and girl. She blocked me from getting on the train as the door was closing. I thought she was a tourist unfamiliar with subway travel so I was somewhat forgiving and gracious trying to get around her, but she was hard to budge. Then her guy friend blocked my way from going down the aisle by standing in the middle holding on to the poles on both sides. As I would try to go one way, he blocked me with his body, and so we danced back and forth till finally I just shouldered him out of the way. When it was all over I noticed my pouch was open. But, the only thing in that compartment for looting was a pen, lip balm, and eye drops, all of which were still there. :)) When I'm in a congested, unfamiliar territory I move my billfold to an inner sanctum behind a clip and a zipper.
A fellow passenger on our boat, I'll call her passenger #1, wasn't quite so lucky. In Florence she was with two female companions. She noticed what she thought was bird poop on her friend's back. Man #1 in the crowd offered passenger #1 a Kleenex to wipe her friend's back. While doing so, man #2 in the crowd sprayed the white, fake, bird poop on passenger #1's back. A random woman in the crowd announced, "There, he's the one who squirted you!" So passenger #1 ran off to catch man #2, the squirter. She did, indeed, catch him, but then she didn't know what to do with him. Meanwhile, the random woman in the crowd took off with passenger #1's purse. The good news--her billfold was not in her purse. The bad news--she had taken off her diamond when her fingers began to swell and it was in her purse.
The moral? I guess is to just be careful.