Thanks for the explanation. So presumably the person involved was intending ultimately to do something involving some market that uses WETH rather than ETH, and was unwisely testing how the system works with ETH worth half a million dollars rather than five dollars. (Or possibly they changed their minds about using WETH for some purpose, and so just wanted their ETH back?)
Yeah, having done this myself, a use case might be:
1. Buy ETH
2. Convert to WETH
3. Swap for TOKEN
4. Hold TOKEN
5. Swap token back for WETH (hopefully made a profit there)
6. Convert WETH back for ETH
I did this using Metamask / Uniswap so it is all done for you. So I had no need to understand how the contract works. Also didn't have anywhere near $500k!
