They're not offering thoughts to Ronaldo at all mate, you can do that by taking a moment in your own thoughts or prayers. Everyone knows there's absolutely no chance of him 'accepting' anyone's offer.
What people are doing is showing other people how much they care. It's become a part of social media that just keeps growing. They're perfectly entitled to do that as I'm entitled to disagree and find it strange.
What next, a thread offering thoughts to a Chelsea player because his grant's pegged it?