GBH,
You are too idealistic.
Low life are responsible for thefts. If I lost a colony in winter and went out and nicked a replacement, would that be checkable by registration? I think not. My colony count is as expected.
If I do an A/S a couple of weeks ago (or less) and someone loses a colony to theft and my colony count is up by one, am I guilty? I think not. If I have a hundred and fifty colonies and, oops, I miscounted by one, am I up for a fine. I would hope not.
If I didn't have a colony until last week and register it, am I guilty of theft even though it was a swarm taking up residence? I think not.
Certainly some thefts might be traceable - if I were stupid enough to sell them on in the same marked hive, I would be guilty of thieving the hive (but not the bees?).
However the low life could not care less. They have to be caught first, and there the odds are in their favour. There are always those who want bees at cut prices, or nil cost. Registration would not deter those scenarios above, nor protect someone having someone elses marked queen after swarming!
The thread on benefits displays quite adequately that there is a large number out there who wish to destroy or misappropriate possessions. Registration is only a means of controlling the 'industry' as a means of tax collection.
Question now : Are hobbyists part of an industry? No but if the answer is 'Yes', all allotment holders might be next on the list. Tax them for each row of veg planted, whether productive or not?
So it could go on. Lots of analogies. Still would not stop the scum nicking our hives and selling them on for petty cash in their pockets; still would not stop the scum who replace their bees with ours after losing theirs over the winter; would not stop those that start beekeeping with someone's bees.
RAB
more likely uninterested in getting stung by the resulting paperwork. 
