They have raised the VAT before. The result was that the consume sank, a lot of commerces closed, and the government collected less money from VAT than before (21% of zero is zero). People 1) think that is an abuse and are very upset or 2) just can't afford it and start lowering its expectatives (i.e buying chinese cheaper products, instead made in germany) or 3) are forced to start doing all business out of the law just to survive. In the end the harvest is that populism and nationalism is growing in Europe; governments need to spend more resources to fight against the fraud, european companies need to spend a lot time in unproductive bureaucracy instead to focus in selling its products, and nobody is happy.

Europe can raise the VAT as many as they want. They are only shooting themselves in the foot, damaging the growth expectatives of the european companies and carefully nurturing the anti-european parties.