haha forget pickpockets i wear a blazer 24/7 (not joking lol, i wear the same jacket every where i go)
it has inner pockets and that's what i use
Okay. Wear a lovely warm blazer in sweltering Mediterranean sun in the crowded stoney capital of Italy in the middle of a hot spring.
(For an idea of how crowded Rome was, I was there during the inauguration of the new Pope.)
Blazers are fine for most places, but they're too uncomfortable for everywhere.
I generally had to balance wallet, phone, camera, map and passport photocopy between my two front pockets (Which have buttons) and the zippable inner pockets of my rain coat (which was used the day after the inauguration, when it rained).
Never put anything valuable in your backpack.
And when you do get in the dodgy crowded areas of Rome, you end up going Tourist-mode and wearing your backpack on you front, even if you just have something like two 2litre bottles of water in it.
