BS, I can only assume that the non-self-loading freight had paid for the belly equivalent of a first class ticket, it could well have been urgent machine parts worth quite a few £$€ at the other end, my guess would be that in these days of video conferencing / telepresence, there is a lot that passengers can do without needing to fly, but specialist equipment that is only made in one place must surely have a much greater urgency.
Thanks everyone for the interesting replies, I certainly wasn't suggesting that AY / HEL had any special policy, it was just something I hadn't seen before. If it happens again I'll watch very closely how far, if at all, the a/c has actually got from the ramp.