I have very mixed feelings about that stadium, (and the Raider's stadium linked above).

They're marvels of engineering. But, what a cost to get some pretty grass. Especially the Madrid implementation - not just the engineering of the lifters/underground facility, but the ongoing electrical expense running all those lights and irrigation systems? Maybe it's really just a drop in the bucket of building a massive stadium, or running a professional sports team, but I can't help buy think we (humans) have our priorities all mixed up.

I am amazed by engineering, but at same time question the resource use and decadence of it...

Oh, you're right actually - mea culpa. I was distracted by the Camp Nou renovation, you're spot on. Although I'm sure Barca will have something equally wondrous.