I think people can manipulate their own physical appearance in certain ways to attract others of similar appearance - and therefore an assumption of similar personality and lifestyle. Projecting a particular look can act as a kind of 'filter' to narrow down a desired social group.
I think we all make assumptions about what people are like from their appearance alone, and often that assumption is correct because those people actually desire us to think exactly that. Conforming to fashions, covering the body in tattoos, pumping up a muscular body, dressing up to look like an academic, etc are all unspoken messages projected outwards for to others to see, or internalised to establish self identity - or possibly both.
Having said that, I have often found in the work I do, that there is a kind of dissonance in the personality behind the intended appearance. For instance, an aggressive exterior sometimes belies a vulnerable interior - the exterior says "keep away", yet the personality behind it is only too glad to have someone to talk to.
In every case - bar none - it has always been worth trying to find and communicate with the person behind the external appearance, no matter how hard it seems.