Whilst it may appear a little selfish:
For a perm event, I have no want or need for a brevet card. Rides such as on CamAudax are validate by GPS, so I pay my entry online with a date and then send the GPX file when complete (remembering to have two GPS devices on the go in case one fails).
If other perms follow suit, I would happily do the same to enter them and keep the organiser happy. Otherwise I'm frankly not going to bother with the hassle of buying envelopes and stamps, sending them off in advance for a card, sending a cheque etc etc, its much easier to download the route, fire off a DIY by GPS and in the notes section credit the perm event. I also then have the option of entering with short notice depending on the weather.