Always surprises me a bit because it seems to me like those large corporate players don't necessarily need all the features offered by Ethereum (or Bitcoin), especially proof-of-work, since there's enough non-adversarial cooperation between them that a simple distributed ledger with traditional (efficient) consensus mechanisms would suffice for most of their applications. They wouldn't have to deal with the drawbacks…
Big-corps sit on piles of cash. They have an "innovation department". They have VC arm. They throw money in accelerators, they organise fintech hackathons, They invest in small startups. They do many a strange thing with their money!
EDIT:
>just participate to get in on the hype
This.