It's not neccessarily sociopathy, but points to a lesson the be aware of who you hang around with.
I heard a stat last year that said that most people make within +-10% of their 5 closest friends salaries. It makes sense when you think about it. If you're hanging out with people who work dead end jobs and simply get blasted every weekend your most likely going to be doing similar things. Likewise, if you hang out with people are always coming with ideas for companies and following through you'll likely be doing same thing.
We have to beware of things that "make sense," especially where cause and effect come in. To me it seems much more likely that people hang around more with people who are in similar circumstances. Since the people you spend the most time with become your best friends, it's no surprise that people will have similar incomes to their best friends.
Please. Some people care about their career more than they care about their relationships. How is this any more "sociopathic" than (for example) someone who neglects friends and family because they're working 16 hours a day?
"You need to have close friends that are at your stage in life and higher, and for that, you have to leave the ones that stayed behind back."
...is not the same as being friendly. It's actual sociopathy.