I knew it! They can't fly in a straight line! Bloody birds...
That is an answer to the question: Why is my beer getting less when standing outside
...But they don't drink wine. Apparently.
http://i.ytimg.com/vi/7adorUbO7EI/maxresdefault.jpg
I can already see some particularly useful real world applications for this phrase.
But they do not drink wine !!! Why ???
"This beer is for the birds!" Must be some pretty bad beer...