Because that's a what a loan is. Something you pay back. There are special rules for accessing it early because you get special tax breaks while funding it. Why is that hard to understand?

It doesn't "have to be" bailed out. What are you even talking about?

Ok, so you don't want to invest your 401k in the stock market, but...you do want to invest your money in the stock market because that has had gains? If you want, you can put your retirement money in gold. Or cash. Or foreign currencies. Whatever, you control it. If your point is that there's nothing good to invest in, then don't participate in a 401k. Unlike Social Security, there's nothing forcing you to.

I've had employers that let you trade benefits for wages. The point is, there's nothing preventing it.