The ANSWER:
1. So it can fit into your fridge easier.
2. I don't know, but it has something to do with oxygen.
3. because building is always going on, whether it's fixing a problem or just upgrading a piece of hardware--it's always happening!
4. Because people are stupid and they're too lazy to walk to the bars themselves and others have a designated driver who's the laziest of them all and won't get too drunk because he won't want to put in the extra weight of picking up more than 2 bottles of beer.
Hope I answered your questions!