I was surprised about this decision from them as well, but it is actually realistic if you think about it. No one can sue them since that is how BTC should be used in my opinion. Because we are paying in BTC equivalent of USD order. They should refund us same amount of USD but in current BTC equivalent.
LOL everyone is happy when it works out this way but they all shit the bed when they get less BTC in a refund because the price went up.