[strongvigilance]

There have always been middlemen, as, especially with less liquid instruments, there won't necessarily be equal supply and demand from "natural" buyers and sellers. As markets have gone from floor trading, to point+click on computer screens, to automation of different levels of sophistication, efficiency has improved - people complain about HFT stealing pennies, but in the past, someone was stealing quarters. The difference is that the skills required have changed tremendously - a few years ago, it was all about being well connected or going to the right school - now it's all about how good your code is.

It's not particularly surprising that the loudest anti-HFT voices are guys whose profit margins have been killed by it.

Disclosure: my profit margins have been killed by HFT...