Being able to store a vaccine card/covid pass in the wallet app is kinda neat. I'm in the UK and opened the official National Health Service (NHS) app to view my covid passes as I'm traveling to Qatar on Friday. When I view the covid passes in there,
I get the option to "Add to Apple Wallet" which I'd not seen before (I just updated to 15.4 so I guess thats why I'm seeing that option now).
It just means that, after adding them, I can double-click the side button while at the airport and quickly bring up my covid passes for any officials that want to see them. Tip: If you're doing this you need to add each pass separately - so in my case I have three: my two vaccinations, and the booster I had in December.
Oh - and I still wear my mask when in shops, etc. in and around London. I don't care if anyone laughs at me