Shopify/Venmo purchases say Billing address is same as Shipping address

Most purchases on our store are gifts, so the billing and shipping address should be separate. When people pay with PayPal or Venmo, they are (understandably) not prompted for their billing address. But then they see a note in their confirmation email indicating that the billing address is the same as the shipping address, which causes them some concern.

How can I prevent or modify that message?