That's not a great analogy. Your registrar is bound by a strict contract, in some countries it may even be telecom legislation, and your domain is legally yours (again, within contract bounds). While they need to delegate it to you, they cannot arbitrarily suddenly give it to someone else.

BBC.co.uk belongs with the Beeb, anything else would be considered an attack on Internet infrastructure and treated as such. You cannot compare that with the power Google has over Chrome. It is theirs to do what they wish with.