We are all influenced by our surroundings and the prevailing assumptions of our (sub)culture.
For ὑποπί̄νω, LSJ mentions an additional meaning "drink at dessert" and cites "Ar.Av.494, Pherecr.153.5, X.Cyr.8.4.9, etc.". A consultation of these passages and the absence of evidence to support the "etc." shows that this meaning is the result of eisegesis, and, perhaps, the Sitz im Leben of the lexicographer. In particular, see N. Dunbar's Aristophanes: Birds ad loc. for the lack of evidence for this meaning.