@Bike:
If you are not aware, many pilots in Wizzair are not employees, but "service providers" (call it freelance or mercenaries, it's todays reality, and not by choice). These freelance pilots have no pension scheme contribution from the company, no medical coverage when they get ill, no personal insurance supported by the airline. They also must take care of their own taxation system and declarations (as is written in some contracts "solely responsible" for income tax). Of course it may be seen as an advantage, but the reality is that when you contribute to income tax in your country of residence, you get some benefits in return, maybe unemployment benefits, social security or retirement, you name it.
In April last year, Wizzair has decided to take money from the pilots wages in the name of their new Swiss fiscal office address. Some received amendments of contracts to sign, some not, but in 12 months it equals to the second pay cut. The difference with any other form of income tax? The pilot gets NOTHING in return! No social security, no retirement scheme, just that right to pay tax! So pay for what? I don't know, and nobody can give a plausible (plausible in this sense means not take pilots for mushrooms) explanation.
The subject of tax has been raised in another thread I believe.