I should have added this to my original post, instead of a new post, but it in a lot of ways, it's a separate topic to the frequency and duration of hanging out with family.
The first is chores. While somebody brings a dish they made to a family event is extremely common and at least an offer to help with dishes is expected, the degree that Brazilian guests chip in to help with chores just doesn't happen that often in the US.
The second, and more complicated, is paying for things. Generally, in the US, whoever the host is pays for everything except for whatever token dish or bottle of wine or whatever the guest brings. When it comes to going out for restaurant meals, my friends and family there tend to practice a sort of socialism: whoever makes the most money, generally pays the most often. And it's usually one or two people paying for the whole thing, rather than splitting the bill.
While I grew up solidly middle-class, all my immediate relatives are now comfortably upper middle-class and I tend to be the most "poor," so rarely pay in family situations.
Also, when I go out with friends to a bar in the States, very often it's just one person who pays, and there's an informal rotating basis on paying.
I must admit I found it really odd, after spending a few days at the pousada of my partner's cousin, to be effectively presented with a bill. The expenses were added up and divided.