Legality of extra airline charges queried

GIVEN the possible illegality of many airline charges and the increasing arrogance with which they impose them, I am concerned for the future of low-cost air travel.

I decided to avail of one offer from Flybe to the UK. The return flight was €42, so I pressed ‘Continue.’ The next thing that was added was over €60 in ‘Charges and Taxes.’

Unless they can provide an accurate breakdown of that sum, I believe this charge is possibly illegal - simply a little extra profit on every passenger. Then they added €3 each way for my case, as if I had a choice about taking a small case for anything over two days. And they appear to have added something else for the privilege of them allowing me to use my credit card. How did they expect me to pay without using it?