It couldn't, of course. Neither the numerous demonstrations against austerity could have changed anything. If, however, the Spanish protesters had a bit of economic knowledge, they might find a cause that is well worth to be rallied for.
Just look at this:
In Spain, it takes weeks to start a business. It's a lengthy process, it's complex (forget online procedures) and it's expensive. If the Spanish demonstrants really wished a change for better, they would demand a major reform of the Spanish law on corporations and the relevant service institutions.
I know, corporations are not sexy. Shouting political slogans is apparently considered as more fun in Spain.