Hello and welcome to the site. Thank you for your question.As I see it, the money held on member's card is like a float. The member can use the card for usage at the bar and/or with the caterer.The card is just a payment method similar to one using a credit/debit card to make a purchase instead of paying cash on the spot..The answer to your question "If the members card is used to register the payment for the caterer's supply and the amount is the passed onto the caterer at a later date by the club who is responsible for the vat transaction?"
It is the caterer who is ultimately responsible for the VAT transaction being the organisation making a taxable supply. The Club has merely passed the cash on to the caterer and taken the money from the member's card for goods supplied by the caterer.
I hope this is helpful and answers your question.
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