I see this as a metaphor for the North American society. Waste is everywhere. Not "convenient" for you to save something? Throw it in the trash.

Food is wasted. Energy is wasted. Products are wasted.

I heard Guy James say something last night that I totally agree with. He said that future archaeologists who will be going through our trash heaps trying to study how we lived back in the 20th century will be amazed and appalled at our tendency to throw away perfectly good food or items.

And the Chinese owners of this restaurant are probably only two generations away from having relatives who starved to death or never had enough food. In some societies it's considered almost criminal to waste food.

Even if you use the argument "well, I paid for it, so I can do whatever I want with it", realize this.
It took energy to produce that thing you're throwing away. And energy to haul it to the dump. If it never gets used, that's in effect throwing away all that energy.

And from a charitable point of view, think about people who who could use this stuff. Spend less on things for yourself and donate to a food bank if you're throwing so much away. You'll be helping someone as well as reducing the garbage burden we already have.