a little left

Why do people always feel the need to not completely finish things off? It is one of my many pet peeves and extremely aggravating. There are two different situations common for this:

1. I'm too lazy - I hate when people leave a little lemonade, kool-aid, or other drinks made from powder just so they don't have to clean out the pitcher and make new stuff. This also applies to milk at work where people don't want to be responsible to stick the carton in the recycling. Unbelievable!
2. The bottom is bad - This is when people will open a new bag of chips, bottle of soda, or something along those lines (at work, a new chemical) when there's still a little bit left in an already opened one. I guess they think that the bottom or last of the item is bad. Why else would they do it? It's so senseless. I hate multiple open containers of the same thing.

So next time you're about to open something new when an old one's open or leave a little liquid left, rethink it. Ask yourself why you're doing it. I assure you that you'll come to the conclusion that it's senseless!