Originally Posted by johnsma22
I suspect it may be due to the presence of unfermented sugars still remaining in homebrew. The commercial brews are more than likely not under attenuated, therefore there are no unfermented sugars present to attract the fruit flies.
+1, it smells sweeter to them.
had this happen the other day myself...left a glass out for 3 minutes and came back to find two drowned fruit flies.
btw, throwing malt out into a pile in the backyard will also attract and breed fruit flies. millions of them...