I apply, get eth, cashing out by selling it to someone else, then get hit by a buss or just ignore you.
Now, in what way can the system enforce that loan?
If you can get the eth from someone that gave me money then they are not going to give me money in the first place. If you say, sue someone in the real world that's fine. But, the smart contract did not actually do anything. If you say I need to put up eth as collateral then you did not give me a loan.
If they went to the work of creating digital contracts and didn't consider escrow, that seems to be a fairly significant omission.
Escrow accounts are fine if I am doing contracting work, but that are not a loan.
If every year your coin splits so now you have 2 coins then 4 etc no money was added. I can have 10^1000 in a database, but that's not new value.
https://github.com/ethereum/wiki/wiki/Proof-of-Stake-FAQ
Staking doesn't produce new coins. It pays dividends from transaction fees. I.e. actual economic activity.
Lets say I Buy '1,000' tokens including a 10 token payment for a transaction fee for 1$. Now A had 1,000 tokens and now has 1$, I have 990 tokens and another group get's 10 tokens. But, notice that other person(s) got tokens not money.
If I got to keep 1,000 tokens or someone else get's those 10 tokens nothing changes because nobody who has tokens got any money. The only way people with tokens get money is if they sell some number of tokens minus a fee to someone else. It does not matter of all 10 tokens go to a miner, or miners get 5 tokens an 5 go to 'investors' or what not.
It's still a (edit: negative sum game) and contracts don't change anything about this.