Membership Cards and Stocard

I am trying to cut down on the number of membership and store points cards I carry around with me.  With loyalty and credit card style membership cards increasing in number, I am experimenting with keeping details of such cards on a phone storeage app. called Stocard.

Most companies will now accept these 'digital copies', and will either scan the bar code directly from my phone, or if it is an older style scanner, will key in the card number.

If I scanned in my Caravan Club membership card, would wardens on site accept this instead of me showing my actual membership card?  No doubt we will all be able to speculate, but it would be useful to have an official response.

David