Awesome character that i don't think you understood
He was been in a long time marriage, which seems to have lost passion but yet he remains faithful to her.
He is related to doing whiskey commercial in Japan instead of doing more meaningful work in the US to provide for his family, thus sacrificing some integrity in his career perhaps.
He is far away from home and his family culture shocked in a foreign land.
He is not very inspired working in commercial.
I didn't see any smug look on his face.
also he is Bill Murray so anything he does is awesome haha
-It's only after we've lost everything that we're free to do anything-

here here - this is murray's finest nuanced work. The original poster really kind of missed the point by hitting it exactly "i suppose that's how some foreigners may behave" yes he was acting !!!! i love this film its top 5 film of all time for me and let me tell you the other 4 change all the time
Its just a ride baby,

Hmmm I may have to conduct a Bill Murray marathon, but I consider his casting here to be sheer genius, and it resulted in one of his finest roles ever. He is clearly a fish-out-of-water, making the most of his isolation, a viewpoint from which he is perfectly placed to make such smug observations. He is a guest of the Japanese, adored by him, beholden to them (for a paying gig).
What's is he to do?

and that, my liege, is how we know the Earth to be banana shaped.

He's supposed to be an action movie star, what do you expect?

He's not exactly a likeable guy, and he's not really meant to be. I just re-watched it last night, and for most of the movie, he's smug, condescending, sarcastic and dismissive.

thats rich coming from a weird looking mouse with a mustache!

Said the kawaii chan weeaboo japanime nerd.
Less than forget. But more than begun.