Why does the *upbeat* music work so well in a horror movie like this?

I'm not referring to the entire soundtrack, but two tracks in particular:

1. The track used during the trucks and car scenes. I believe its called "La Caccia"

2. The track used during Peter/Roger's shopping venture early in the film and also during the finale when the motorcycle gang breaks in the mall. Not sure what the title is.

Compared to the rest of the soundtrack, these two tracks contrast with an upbeat tone. With all the horrific things going on, the pandemic spreading, etc. I think it's a weird choice on paper, but when you watch/hear it, it somehow works. And this is the only horror movie I can think of that has tried something like this. Not even the stupid remake attempted it.

One thing noteworthy of mentioning is that these two particular tracks are only playing whenever our 4 characters are taking a stand, so to speak, against the opposition.

The "La Caccia" scenes (securing the mall with the trucks/car) are my favorite. The characters are taking a stand, not to stop the epidemic, but to build a better life for themselves alone. Because that's all they can do. The world is falling apart around them, but that's out of their control, the epidemic is bigger than them, it's everywhere. But that's not stopping them for creating the life they want to live. That's kind of what La Caccia conveyed for me.

Anyone else like to comment?

SPomposello on HubPages
http://spomposello.hubpages.com