Front pants pocket not safe either.
I got my wallet lifted out of front pants pocket. I just stepped on a crowded metro, my spouse saw a man step in behind me, then back off just as the doors closed.
I missed it 10-15 minutes later when I tried to make a purchase. I never saw it again. Cancelled credit cards, used spouse's cash, borrowed from our friends (they are still friends) and had a great time.
If you read anything about traveling in Paris, there is plenty of warning about pickpockets - and there are signs all over in museums, metros, ane even Versailles. But I still felt real stupid. I carried minimum in my wallet -- ID, one credit card, some cash. Nothing else.
Next time, we really spread our money around. Both wore money belts, put money in socks, put hands in pocket around wallet on Metro. Carried minimum cash.
Friend put his hand in his pocket and found another hand coming out! Again, man just stepped off train and door closed.
These are the experts --- but I love the metro and love Paris.
I sure wouldn't have fought him or tried to restrain him. That can get you injured, and for what?
Glad it turned out well for you.