Yeah agree. Not that I'm sticking up for the Spanish Football Federation but this is likely to be more about the Saudis chucking money at them, rather than them prostituting themselves to the highest bidder. I suspect the Saudis approached them and said 'hey, here's X million euros if you bring your Super Cup to Saudi'.
Via work, I've worked on the Formula E in Saudi in December and a horse racing event there next month. They're literally chucking money at major high profile sporting events to bring to the country. It's all part of the kingdoms bid to change international perception of their country and they have a plan to vastly improve the whole infrastructure and perception of the country by 2030. I think they've seen what's happened to Dubai and how that's boomed in the last 30 years and are thinking 'I want a piece of that'.
They're trying to shake of their human rights record by bringing such events as European Tour Golf, Formula E, the Joshua boxing match and now this etc as well as letting woman drive, as part of this 2030 drive.
Still doesn't make it right for the Spanish FF to say yes though but money talks. I'm surprised we didn't see more in the press about uproar from the fans of the 4 clubs taking part.