> Why should I use Firefox, or any other browser, from a standard consumer prospective?

Because your techie friends tell you to. This moved people off of IE6 to Firefox and this is what initially got people to move to Chrome from Firefox. Google's muscle on its web properties did the rest. Even you admit that Chrome is only marginally better on all benchmarks. For me, it's worth it to help your non-technical friends keep the web a bit more open by making them wait 0.1s (or however much longer) to open Facebook.