Most credit card companies view a transfer as a cash advance, so you'll get nailed with fees if you swipe. I refuse to use my checking account number on anything, as it takes longer to get your money back on fraud.Venmo, Zelle, CashApp, Apple Pay, etc. all work the same way. It's as good as cash. No fees, and the buyer can't reverse the charges later so the seller is protected. For face-to-face transactions, it's good to go. For shipping transactions, I would avoid as both a buyer and seller.