New feature alert: Add your loyalty cards to Curve

Shell gas stations clubs: V-Power club and SMART club. I wonder how well these two loyalty programs work with Curve.
V-Power club card issued by Shell in one European country, SMART club card in other European country (both continental Europe). V-Power club card has bar code on backside. SMART card none.
Curve app doesn’t offer scanning the card if to select “Shell Clubsmart” from precompiled list of loyalty programs.
The try to use above cards through Curve this week failed.Cashiers needed to scan bar code from my smartphone screen. Curve app however doesn’t present and bar code for these cards registered with Curve app. It only shows card number.
Additionally loyalty cards registered with Curve app seem to use Internet connection while scanning during transaction. Cards registered to app are not presented in app if there is no Internet connection. Is this a desired feature?