I've more than once ..
had people claim they never got something want money returned or another sticker or t-shirt when I know they got them .. so, I want the transaction final when it leaves my hands .. plus, I price my stuff cheap enough , not going to
lose another 3% ..

Had one clown, insist I send them 3 times, each time he said he never got them .. paypal still took my money back .. I've had good luck with most people , few rotten apples