Plus reporting which laundry machines are in use, and paying for their use, are two different things, so an app could show you which machines are available, but

Plus reporting which laundry machines are in use, and paying for their use, are two different things, so an app could show you which machines are available, but the machines still let you pay with coins. The GPs argument is similar to how full anti-user lockdown of devices is justified for some minor security benefit that could have been achieved without said lockdown.