They seem to think they will be working class for the rest of their lives and there's noticeable hate/resent for the rich.
Being an immigrant, I didn't notice any of this stuff. I didn't notice the dismissive polite attitude, I thought it was just politeness. You know, when someone wealthier talks to you, they're polite but there's subtle signals that they consider you "inferior".
I only saw the opportunities, of which there are plenty. I didn't see classes, I just saw that it is possible to go from working class to upper class, much easier than in most other EU countries.
I did start noticing these "subtle signals" after a year and a half or so, but honestly I just decided to ignore them. Since I would always be a foreigner, people would just cut me some slack for not understanding stuff (this also happens in Japan afaik).
Clothes play an important role, surprisingly (OK, maybe not that surprising). If you're in dirty workwear and a hi-vis vest, you're pretty much considered bottom of the barrel. With the right clothes, you can turn into anything from a "chav" or a middle class manager to a millionaire (though you also need the attitude - no slouching, make eye contact, etc).
Just some of my thoughts.