Indeed, those who are willing to go out and drink are more tolerated by society than those who are more introverted. This is probably because the former are willing to go out, drink, meet new people and socialize in general. There's a strong difference and the way society treats them is very discernable.
Someone who is a great employee may nonetheless not have the interview skills necessary to wow someone for a job because she is more introverted. So a less-than-qualified candidate who may have better interview skills (i.e., be more extroverted) may end up getting the job at the expense of the more introverted candidate.
Extroverts are the bubbly people who are fun to be around and tend to be easier to tolerate. Extroverts are also more likely to be out in the limelight so they are more visible and seen as more "normal". Many people simply don't understand the introvert personality and find those people to be less friendly.
Yes, society tolerates extroverts more than introverts because they are preferred in our society. We are gossips and busy-bodies. Those who tell all and wear their hearts on their sleeves satisfy our need to know. Those who have decided to be private are subject to scrutiny and distrust from society.
I am a high-schooler that is obsessed with social-networking sites. Depending on your stance in society, you will not see. As a teenager, I can tell you that in our little close-knit adolescent society, being an introvert is quite accepted. Visit Tumblr. You'll see quickly that it is very acceptable if you're a teenager. That is why most of us who are shy stay glued to our cell phones. Our online society accepts us, while the real world does not.