Ricer is a state of mind. You can have an F50 and still be a ricer if you do ricey crap to it and behave in a ricer kind of way.
BOVs make you a ricer just like owning an SRT-4 makes you a retard.
Its not that the valve or car are ACTUALLY linked to being a ricer or a retard. Its just that the majority of people WITH them, are ricers and retards. So it gets a whole bad stigma. Plus ricers, the first word out of their mouth when they think of a turbo car is "bov"