Being like Spanish politicians are, would be much worse.
The protests are against the monarchy, and in many cases against the Spanish political and institutional system. No serious democratic country, can change the form of State every 30 or 40 years ... and Spain in the last two centuries has had too many such experiments.
The leftist movements, republicans, independence groups ... always organized large demonstrations and make lots of noise. But if they really want changes, they will not succeed with banners and shouting, it must achieve with elections and in the Parliament. They are experts in promising things and tell people what they want to hear, but that often collide with the reality of today's world.
The economic crisis has increased the discontent of the people, especially the youth with the system... now the head of the system changes, and thus gives way to another generation to another way of seeing things and that will give way to change.