None of us live in an enclosed capsule. Societal pressure does
exist!
The examples you give are a tad too extreme to be good examples,
methinks! 
I mean, you're choosing all examples with a
revolting factor to it! 
Of course, we can always choose to stand strong and not listen to
what everyone else says about what's 'in', what's kewl... however,
if you keep facing dissent and disapproval because of say, the way
you look, sooner or later, you'll succumb to the pressure or break
down under it. Guess what happens depends on how strong your
self-esteen and self-confidence is and if there are other big
stressors in your life at the moment.
Often, although we love to exert our own individuality, a
devil-may-care, joie de vivre kinda attitude, the opinions of
others, depending on who they are, DO matter to us! We do have
family and close friends and the closer we are to them, the more
we'd love to feel accepted by them.
Ultimately, yes, it boils down to personal choice. But never
underestimate the power of peer pressure! It can wear down even the
toughest bloke!
