There are things in this world you cannot buy, you know.
What's the difference with PoW? You spend more on equipment, you control more. You can collude with other large miners.
Those who develop new equipment, might not sell it to those who are currently at the top.
Not everybody sells their share of control for profit.
So can we expect one company to develop super powerful ASICs and totally hijack the PoW network? Wow, that's scary. In PoS anybody can be a miner with their normal computer, I say it's very attractive to users. Users drive the price and adoption, not miners. Crypto should be user-centric, not miner-centric, to be successful. And that's where PoW fails.
It's not about profit or returns, it's about control.
You will get guaranteed food in a zoo too, but you'll be missing something essential, wouldn't you?
ASICs can be challenged with newer ASICs, stakes (once big enough) can never be challenged.
Would you like control of the money flow to be a competition or would you like it to be in hands of a few forever. If you prefer the latter, just stick to fiat and be done with it.
EDIT:
I wouldn't be a crypto geek if I couldn't read hidden messages in random data.
Take a look at this thread, it's a new song about Bitcoin.
https://bitcointalksearch.org/topic/welcome-to-the-blockchain-857195
Here is a Bitcoin address (I added white spaces for readability)
1C4 iVs2E659ksBK8gVEyQw229 ZoESC oyK1
1C4 - apparently Satoshi needed only one C4 to plant at the perimeter of our fiat zoo some 6 years ago. If you play video games you'd know what it means.
iVs2E659ksBK8gVEyQw229 - time it took before the smoke settled.
ZoESC - we now have a hole in the perimeter and can escape our zoo.
oyK1 - everything is gonna be o k !
Good day!
PS: The word "mining" has definitely something to do with perimeter disruption, besides its usual interpretation. Thus "miners" are those who will disrupt every perimeter they encounter on their infinite way out from a zoo within a zoo within a zoo... Hmmm and what if there is no zoo?