this uniquely charming way of sitting is said to have roots in a time when television sets where not broadly available, and soap operas were especially popular - cariocas would watch popular soap operas in restaurants and public places, and they would sit side by side to get a good view of the screen.

eventually televisions sets became available to everyone, and people could watch any programming at home, but the tradition remained, fitting very naturally with carioca couples - generally very affectionate, couples who sit next to each other can hold hands, rub each other’s arms or give affectionate kisses.

this is so much part of the local customs that at some more traditional restaurants, locals might assume a couple is in an argument if they are not sitting next to each other.