Perhaps jealousyWe can enjoy it more than they do and turn off when we want and don't have to get up at 4am in the winter
I've never really been into the registration malarky, much more just admiring 180,000kg of aircraft rolling down a runway to 170mph and deciding to get airborne and the sound of 60,000lbst being produced.
HD is certainly one of the friendlier (ex)professionals
I'm glad to say I have met some mature and not so mature professionals who aren't the type who degrade spotters at every opportunity.