jonathan18:

 

'Cards' don't weigh much when added to Google Wallet, Stocard or equivalent, just saying...!

 

I haven't carried a barcode-equipped card in my wallet for a number of years... 

 

Not everyone is a tech expert like you.

I have never participated in any of these loyalty schemes because I hate the idea of carrying around a whole lot of cards and having to keep track of how each scheme works and which card to use at which outlet.