It’s a gesture of respect for a civilian. We don’t have to salute. No one is going to bust us to buck private if we don’t. We salute things, people, whatever because we want to. Because we hold them/it in high regard.
Each of us is entitled to care about those things, people, positions, symbols we hold dear. Saluting expresses this to the person/thing/symbol and reinforces our reverence.
What I salute or don’t salute may be different from you. That’s OK. I have no problem with what other people care about, even if they are a nutter.