The management chose to ask the government for those guarantees, the government chose to provide the guarantees. The employees just negotiated the best deal for themselves and their families which they could, this is their legal right in a democratic country. As a shareholder you appointed the management that agreed their pay, if you didn't agree you would have sold your shares, if you didn't like the pay in the first place then you would not have bought the shares.
Unfortunately in Europe the right of Pilots to collectively negotiate a fair contract has been removed by ruthless management's who take advantage of discrepancies in the laws between the different countries. Recently some companies were targeting pay for 737 captains at below 50,000 GBP, that is the same as London underground train drivers. Contrary to popular belief operating jet aircraft in different environments and weather is a significantly more skilled job and responsible job than running a train on rails around a city.
Maybe BA have about the correct and fair scale for this job, but in my view salaries should be set by collective bargaining.