Politicians occasionaly get elected because of the amount of backing they receive (financial or otherwise).
Some might feel they owe a debt to those that help them get elected.
How they repay this I leave to your imagination.
Aviation contractors are small fry compared to the big boys - you might ask about the recent British news items with tax holidays or Microsoft and others in the Irish republic with CGT. ( as Merkel has been complaining for several years).
IMHO asking the authorities about the anomalies of aviation contractors when there are MANY using the same loopholes to avoid tens of millions is a waste of time...
