Last year I enquired about some replacement tweeter grilles for my Monitor audios via email. A couple of exchanged messages and Three days Later I receive a jiffy bag containing a pair of tweeter grilles sent absolutely free of charge. Nice one MA!
The only thing they might not have done "correctly" is told you how much they were going to take from your card before they did so. £3.50 is not unreasonable, there's postage and someone's time. If they told you how much it was going to be, you'd have the option of accepting or not.