Paper chasers - Banks don't exactly get sent a list of every single item you bought when you go shopping all they see is a charge, and the store's information. (Unless I'm wrong about this).
But either way as long as it isn't to meet a spend requirement to get a bonus I don't see it as being an issue at all.
In fact say you use a Visa Card to make the purchase and are purchasing a Visa Gift Card. Then Visa is making twice the money from merchants to use the cards.
Many grocery stores no longer allow you to use a crefit card to purchase gift cards- they accept debit cards only for this purpose. All of the grocery stores in my area recently put small signs at the register stating this.
Their systems will also reject it if you try to use a credit card anyway.
