I'd say they want the chance for a decent future. Raising the cost of a university education takes that away from them. While you may argue against the use of violence to make their issues known, you can't deny them a righteous sense of indignation.
They have seen their futures eroded by massive spending on futile and illegal wars and by corporate greed.
Further, Western governments have increasingly seen education as being a priviledge and also a source of income rather than a responsibility of government to their people and an valuable investment in the well being of their country. A very sad state of affairs.
