I copied it from another of their stores. Supposedly it is:

• "access:eid = BankID" means you need BankID to unlock the door and enter the store

• "access:eid:country = SE" refer to the fact that BankID is only avaible to Swedish citizens.

I agree that this method seems odd, which is why I started an OSM Wiki discussion on both Key:access and Key:authentication:*.