Paradox of Spanish health system

It seems incredible that a Spanish citizen’s health card is only valid in one’s own autonomous community, and that one can’t receive medical care in the rest of the country without having previously formalized an absurd paperwork: the relocation slip, whose real purpose is no other than to put up domestic borders and hamper our constitutional right to freedom of movement.
I meant: it would seem incredible, conditional. It would seem incredible if it weren’t because even the worst blunder is possible in this split, self-apostate Spain; in this mutant country of made-up cunning regionalisms. But since anything can happen here, such are things. Both the kinglets of the autonomous taifas and the central government, in the height of their political ineptitude and ‘autonomistic’ blindness, have proved totally unable of agreeing on a coordinated and unlimber health system. On one hand, because those kinglets are only too eager to label as recentralization –and thus anatemize– any unifying policy a government might undertake, due to their semantic confusion –out of ignorance or demagogy– between centralize and unify. (Pity they didn’t learn better their own language.) Interestingly, by the way, they don’t mind to give away their personal data to Facebook so that Mark Zuckerberg can centralize the information in his servers, but they do mind the different autonomous comunities in Spain to coordinate and unify databases and medical services so as to remove setbacks on behalf of the citizens. And, on the other hand, because the central goverment is always afraid of being called terrible names like centralizer dictators, and therefore, not giving a dime for their people, they dodge the issue for not confronting the kinglets.
But the last straw in all this nonsense is the fact that the European Health Insurance Card (EHIC), which is a reality since a few years now, entitles a citizen from any country in the EU to receive medical care in any Spanish region right away, trip-free. Hence, say, a French spending a few days in Madrid, or happening to go past, will be granted medical attention easier and faster than any other non-Madrilenian Spanish.
And if you think that this is absurd, there’s yet more: since the EHIC entitles the holder to medical care all throughout Europe, then, Spain being part of Europe, leads us to conclude that such card should also entitle a Spaniard to health services throughout all Spain, so that for reciving medical care in an autonomous community other than mine, it should be better for me to hold, before the health centre staff, the EU-supported  EHIC than the limited card issued by my taifa kinglet. But it is not so: the EHIC is valid in any EU country except in one’s own. An absolutely demential paradox.