[6502nerdface]

Arbitrage in general is not a "net negative." It's a net positive, which is why arbitrageurs earn a profit; they are compensated for a service that generates value for someone else.

To quote from Larry Harris' textbook [1]: "Arbitrageurs ensure that prices do not vary much across markets. When prices diverge, they buy in cheaper markets and sell in more expensive markets. The effect of their trading is to connect sellers in cheaper markets to buyers in more expensive markets."

Arbitrageurs effectively "port" liquidity from one market to another. This is the value they provide to others.

Thus I'm not sure I would describe this as arbitrage; or at least it's not the term the GP is looking for.

[1] http://www.amazon.com/Trading-Exchanges-Market-Microstructur...