You won't get many responses because the PC thing is to side with Catalonia, but this is the whole story: a money grab scheme. It's been going on for ages. With B- debt rating, collapsing health care system, and massive public spending on things like the one you mention, they simply need money. Plan post-independence is to seize all public assets belonging to the Spanish state (funds, buildings, public companies, ...), while retaining their first customer (the rest of Spain), pay no tariffs (stay in EU), and no taxes to central state.

Before anyone answer with "but the Spanish state too": yes, same shit, which doesn't invalidate anything I said.

edit: wording