In a Vanguard 500 index fund, there are no front load fees or redemption fees, as long as you keep your money in long enough. They have a very reasonable policy to discourage frequent trading. The bid/ask spreads that they have to pay, are not part of their states expenses, but due to lack of portfolio turnover, those spreads do not amount to much.
Vanguard also makes a bit of money by lending securities for short selling. I believe that they get adequate collateral. Securities lending, apparently, generates substantial fees that offset their expenses to some extent.
Why not, if "management" is mostly automated. Vanguard has a nice website where most customer requests can be fulfilled by the computer.
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