On the Area side of things there really isn't much of an issue with bonding (provided people are planning on staying in the UK) as you would have to work for NATS regardless.
For airports/aerodromes then yes, I suppose you could argue that you get posted somewhere you didn't like and bugger off - but if you were training with NATS then presumably your preferred posting was at a NATS airport who are unlikely to take you after walking out on another NATS unit.