A personal use case: my local gym that issues only physical barcode cards -- I used a different app (similar in this style) that allowed me keep it on my apple watch / iPhone instead

I see, so this is specifically you have a physical, eg, loyalty card that has a barcode, and you want to use the Apple Wallet?

my use case is a loyalty barcode for a major retailer here. they provided a digital version but you had to download their app or take a picture. apple wallet is convenient, u just double tap and the Wallet loads on screen with full brightness to make it easy to scan. i dont have to keep anymore.

but on apple wallet u can't create your own a pass from a simple scan. creatign the ".pkpass" need a signature from a apple developer account.

I have my library card in Apple Wallet so I don't need to bother with the actual card.