>>10
I don't think you even know what a 401k is. You seem to have a 401k confused with employees owning stock in the company they work for. A 401k is not a type of investment, it's merely a container vehicle allowing other investments that would otherwise be taxable to be tax-deferred or tax-free depending on type. Although company stock is one possible thing that could be stored in a 401k, many plans don't even offer company stock (mine doesn't). A 401k can contain individual stock, stock mutal funds, individual bonds, bond mutual funds, any other sort of mutual fund such as commodity, real estate, or foreign currency, or even basic money market for the risk-averse.
And for that matter, the US stock market is not "gambling", unless you try to beat market returns by trying to predict price rises & falls or by overweighting certain companies or sectors. Investing in the entire US stock market, as a whole, over a period of at least ten years, has the highest risk-adjusted return of any other investment class in the world.
Also, no matter how much the value of an investment declines, you haven't "lost" anything until you sell. With a long time horizon, declines in value early on are good because they let you buy in even more at a bargain price.
The US stock market has never had a losing decade... there is no point in history where you could have invested money in the entire US stock market (such as via an index fund) and not had a positive return 10 years later, usually very positive.