Infinity War set a few years after Civil War

Doubt they can do that now he's the most wanted person on the planet. Then again, if Clark Kent can get away with it, Steve Rogers deserves a pass.

Well, everyone is kind of used to that fresh-faced, somewhat military-haircut, red/white/blue wearing version of Cap from the BUY WAR BONDS posters and the somewhat larger than life stuff that was at the Smithsonian exhibit where they exaggerated that heroic jawline and made him seem kind of hard looking. The guy with a dark beard, shaggy hair, wearing green/orange/brown/grey/purple, sticking to clothing that doesn't do anything for his figure, and relaxing his posture, would do wonders. Plus, there is the matter on context. I mean, they stuck Henry Cavill in Times Square, with a SUPERMAN shirt on, his hair styled like in MAN OF STEEL, no glasses, and standing right next to posters, and for over an hour not a single person recognized him as Superman or Henry Cavill, no one even paused or clearly gave him the side-eye to even give the impression they suspected him of being familiar/famous. But no one expected him to be there, so they didn't realize. Heck, I remember a Marvel fan joking on Tumblr that he and his girlfriend didn't realize they had been on a ride at Disney World with Chris Evans and his brother until a couple days later when they really looked at the photo they got of themselves on said ride, and they realized the people who got on just ahead of them to be one row in front of them, had included the Evans brothers.