Actually, the HFT people are more likely to sock their winnings away. Anyway, "I take money from people so that I can increase the national GDP by spending it" is not much of an argument for a socially valuable way of life.
Sock money away where, in their mattress? No, in the bank, money market, investments, etc. thereby increases the available funds for others to start businesses, take out loans, provide liquidity to the market. "Take money from people", you mean engage in a mutually beneficial and agreed upon transaction where you take money and give a product or service... yea not the same as theft.
I don't agree with "mutually beneficial" in either case, and "agreed upon" is murky in the case of HFT and at least somewhat misleading in the case of domain squatting.
And "I take money from people to increase available funds for others' business purposes" is not much of an ethical argument, either.
