Dan's family: shallow, insipid and fake
A crossword competition? With loud cheering when someone gets a word right? A group talent night complete with full makeup?? An aerobics workout that seems obligatory for young to middle-age family members?? Please...
Well, the film was produced by The Walt Disney Company (Touchstone imprint), not known for their ultrarealistic approach to domestic dramas.
Note how the more in-depth and intimate dialogs are reserved for Dan and Marie (essentially the two outsiders) as the communication between family members proper smack of insipid superficiality and even 'WASPy judgmentalism' as one critic put it. The matriarch (Dianne Wiest) and the kid bro (Dane Cook) characters are particularly awful, being the loudest ones in the pack. Worst of all, we're supposed to like these two.
That said, I think family clans vaguely resembling this one exist, including my extended family, with the elder grandparents keeping the ties all together (my uncle in my family). However, I doubt a 3-day long reunion would be as consistently happy and eventful as portrayed in this superficial dramedy. In an actual family clan it would often succumb to dullness and petty infights.
Appreciating a close-knit extended family (complete with sleepover reunions and talent nights) takes a certain frame of mind and character that is actively egoless, dedicated and devoted to traditional family values at best, and insipid, one-dimensional, fakey-syrupy, even delusional at worst. I think those who crave extended family reunions the most are unhappy in their immediate family (meaning spouse, parents, siblings, children). I understand them too but I'm not one of them as I value true intimacy, calmness that comes with a functional immediate family.
(Bottom line: communication with extended family members necessarily lack depth and intimacy as both parties are preoccupied with their own little nuclear family. When a nuclear family is functional, extended family reunion feels like overkill.)