The issue seems to be mainly that of those people who would not normally go anywhere near a railway and either don't understand the rules or don't care because their ilk's actions don't come back to haunt them later (as passengers). It's not exclusively this, of course, but I am getting the impression fro various media reports that it's the casual 'visitors' doing most of the damage.
As a railway photographer myself, I make it a personal (and, to me, obvious) rule never to trespass/transgress and to stop others I see from doing so. A few things mystify me - why is it felt better to be within a few feet of any giant machine for a photo (generally much better from at least a slight distance), why do so many people at stations seem to go to such lengths to try to exclude people from their shots (the railway's 'raison d'etre' is people) and is it a generally-held belief that fencing is there to be scaled (the 'rules are there to be broken' mentality)?
Reluctantly, I have to say that, if it helps to keep heritage workings alive on the national network, I would support banning 60103 (possibly a unique case?) if a combination of timing secrecy and media black-outs doesn't work. As it is, the whole heritage movement is being tarnished by one particular problem. It's a great shame, because the loco should be a great ambassador for railway history and be able to get more people interested in railways.
The wider issue, of course, is society's apparent disregard for low level crime.