"It seems the only reason that the Government has chosen nationalisation is because 'it offers better value to the taxpayers'. This is equivalent to a thief telling you it offers better value to him to steal from you, than to enter into a commercial transaction with you."
The scenario is bit more complicated than that. In this case the thing you own only has value because the 'thief' is providing funding to a bigger entity of which the thing you own is notionally a part. If the 'thief' pulled his funding the thing you own may have no value at all.