The bit with the grandpa was absurd, almost ruined the movie for me.

Yeah, please tell me I am not the only one who thought this was really out of place and ridiculous. Towards the start of the film, when the family has packed up the truck and is getting ready to hit the road, the grandpa is furious by the thought of leaving and they eventually decide to drug him so that they can get him on the truck. Now, this is all fine and fitting for a character like the grandpa - yet what got me was how that scene with him being drugged is pretty much played for laughs. Cut forward several minutes, and the grandpa dies shortly thereafter.
Am I the only one who thinks the way this played out in the film really just made it all seem so absurd?