Nobody is surprised. The FDP knows exactly what they’re doing, which is make as much politics blatantly in favour of their donors as long as they’re in power. They don’t care about what that does to the general populace or even how they’re perceived for it. One or two elections later everyone will have basically forgotten about it again anyway and the whole shtick repeats.
It is not so much that everyone will have forgotten about it and more that they tend to go for first time voters who were maybe 10 years old the last time the FDP pulled the same thing.
I still blame those first time voters for not informing themselves properly before voting. They all should know people whom they could ask, and are old enough to remember, if they only cared enough.