Not 'to trade' but to enter the small world of HFT. Many, many industries have capital barriers to entry, I don't really see the big deal. Just as I cannot start an HFT firm, I also cannot start a toy factory or restaurant without sufficient capital. If you actually look at how much money HFT firms earn relative to the finance sector as a whole, they're pretty small fish. They just pay a lot because they have relatively few staff.