How to react...

Walking around Marina Greens in San Francisco early one mooning, I noticed that the tide was out and to see what the area looks like, I stumbled on this one single bottle sitting there.

Everything else in the area as clean and looking like a scene of low tide.... I don't know if I should get upset that people are so lazy as to just leave the bottle versus taking it with them.  How would you feel seeing this?  Just wondering if I'm just too sensitive to this stuff.