The way my supermarket did it is mail an archive by email and the decryption key as signature required in snail mail to my stored physical address.

Wait .. your supermarket did that? That’s .. pretty impressive, but now I want to know what exactly your supermarket had on you (assuming you had some sort of loyalty card they tracked you with).

Purchase history for two years and classification of what I buy. Yes, loyalty scheme.

Anything other than that? Sounds super interesting, glad to see a place get it right :).

My bank hasn’t heard of encryption and thinks security questions + SMS 2FA are cutting edge. What the hell supermarket is this?

Closest thing is UPS mailing me a PIN to authenticate the address for the My Choice portal.

Fourth-ing the other commentors; what supermarket is this and are they interested in expanding into personal banking?

BILLA Austria, part of REWE.

That's really cool honestly. Which supermarket was this?

BILLA in Austria, part of REWE.

What did you buy?