I can certainly see how one might think that, given this case. But having looked at some consistently profitable strategies, I am quite convinced that there are people with real, legal edge in the market. You wouldn't believe some of the things people exploit, they can very very small things.
I remember interviewing a guy whose whole thing was to make electronic markets in a product at the price where the price increments changed (think 8-9->10<-12-14). I didn't pursue it. Yet another guy found a small quirk in a niche market related to baskets of securities. Quite often they are things that have a cap on the money that can be extracted. A friend of a friend has an obscure electronic strategy that makes him a few million bucks a year, but can't be sized.
Then there is also a whole class of people with some sort of information privilege. Market makers who hear about a big order first (because their broker has got to call somebody first), or participants who are at a natural information aggregation point (people with a lot of connections).
In the HFT space, there's also a whole load of things related to reg NMS rules that ordinary participants are possibly not aware of.
I remember interviewing a guy whose whole thing was to make electronic markets in a product at the price where the price increments changed (think 8-9->10<-12-14). I didn't pursue it. Yet another guy found a small quirk in a niche market related to baskets of securities. Quite often they are things that have a cap on the money that can be extracted. A friend of a friend has an obscure electronic strategy that makes him a few million bucks a year, but can't be sized.
Then there is also a whole class of people with some sort of information privilege. Market makers who hear about a big order first (because their broker has got to call somebody first), or participants who are at a natural information aggregation point (people with a lot of connections).
In the HFT space, there's also a whole load of things related to reg NMS rules that ordinary participants are possibly not aware of.