Redbox knows, they just dont care
It is not an accident that this Redbox app is only offering Always On or Off as location services options. Any company the size of Redbox makes this decision to leave out the "Only while using app" option. So the question is why?
There are two most likely answers: Either they are 1) looking to eventually mine/monetize the location data of their users (presumably to improve services, but also quite tangibly increasing their valuation as a company), or 2) their developers and product team are incredibly inept and overpaid to have not foreseen this backlash against their terrible UX.
In either case, they dont deserve my (or your) business until they stop pretending users are that gullible. Without more thoughtful development of their mobile product, they will dissolve as an entity much quicker than they are already projecting, and if that happens I cant say they didnt bring it on themselves.
Hoozenabunker about
REDBOX: Rent, Stream & Buy, v5.20