German Puzzler - possible answers

He was in uniform.

He had a U.S. style wallet in his pants pocket instead of a European style wallet in his jacket.

He had a suntan or sunburn, inappropriate for the time of year.

He was black. Or Chinese, or otherwise not Caucasian.

He had a swastika tattoo.

He had a tattoo that identified him in some way as American, or a soldier.

Artificial leg.

Probably the real solution has something to do with the crosswalk, signage, or signal and how he (she?) reacted to it.