I think the worst part of this is businesses that do this all have different crappy apps. My gym has their own app that must be scanned upon entry. But their app is often slow and unresponsive, and unpredictably logs out. Often at the entry, a person will be stuck trying to reload the app, possibly hindered by their phone having switched to the gym's questionable wifi. Multiple other people will be stuck behind them, having preemptively loaded the app and QR code while walking to the door.

This replaced keychain fobs with a barcode, which had none of these annoyances.