It's not exactly pity, coming from him, but it is sympathy, an acknowledgement that her Natasha's thinking was wrong. There's something broken about thinking that other people need to learn the harsh lessons that Bucky and Natasha learned during their time in Russia. He can't condone it. She should try to be better. He wants to be better.

When the waitress brings her payment device over, he taps his card to pay for the entire meal and leave a tip, returning the slight smile when Ava asks what it's like out there. "It's... overgrown. Alien. Even wilder out beyond the Abandoned City, past the second fence. I can show you some interesting spots one of these days."

He only nods once in response to the thanks. What he's done today hardly makes up for all the shit she's been through, for some of the shit her Natasha put her through. "Walk you back to the housing building?"