It could certainly happen anywhere, including here in the USA. The Niquab not only covers the entire face apart from the eyes which prevents identification, but the rest of the outfit provides concealment opportunities for anything up to and including a rocket launcher. It also provides a social "leave me alone" barrier, in that anyone, particularly a law officer, who dares to stop and question someone in such garb is instantly in danger of being labeled a 'racist' and having his / her career destroyed as a result.
It already did in Philadelphia about a month or so ago: Three men donned Muslim women's clothing to rob a bank: Click here.
“...in danger of being labeled a ‘racist’ and having his / her career destroyed as a result.”
This will only end when we take the sting out of that word. Someone calls you a racist, say: “Yes, I am a racist, so what?” It is not illegal, after all, as long as you don’t discriminate, you don’t have to like it. I would be willing to bet that everyone is at least a little bit racist.