It depends on the terms of the sale. If your agreement allowed that you could return it, then you could. If the agreement was that all sales are final or did not involve a return discussion,...
They don't "mean" anything, other than the replacement of the normal words that appeared in the original line. Are you thinking of this... "Come to the dark side" it's star wars language, look it up....
According to Wikipedia, the air date for this Family Guy episode is to be announced. Also, Wikipedia states that Something, Something, Dark Side is an hour-long Family Guy episode which is slated to...