When in Arizona, I went to a rodeo that wouldn’t dare check vaccination after a museum fundraiser that required it but didn’t verify. As someone who would like to go to both types of events, a single document would be helpful. If others prefer to constrain themselves, that’s fine. We are discussing privileges, not rights.
Doesn't matter if someone dislikes it - it will never be the law of the land here. Basically everywhere I've been including deep blue cities are moving beyond this idea of needing "proof" of something for months now. What you're advocating for is creating two societies.
If we're going to create two separate classes of people, one of which does not enjoy the same freedoms and abilities as the other, I think there needs to be actual data to back it up instead of it just "feeling like" it's the safer thing to do.