It's a pain in the ass, really. Wallet (formerly Passbook) is very easy to access, and you don't scroll or anything, just flip between tickets. There's no excuse for this not working. It worked in 2015, I used it (Wallet/Passbook) for every single game of the season, and not once was there a scanning issue.
I'm a developer, and frankly, I think they simply did not design a front-end for the mobile side. Looking at the source for the Account Manager login, it's very sloppy (in-line CSS? Are they editing their pages in Word??).