A new deleted scene from the How I Met Your Mother final season DVD reveals the answer to that long-forgotten pineapple mystery.
In the deleted scene, however, we see Ted at The Captain’s house after Lily sought refuge there following her departure from the Farhampton Inn. (This is the episode in which we learn she's pregnant again.)
Once everyone chills out, The Captain stops Ted and says,:"You stole one thing from me, one thing I can forgive. Steal more than one thing, well, that's another matter."
Watch the deleted scene above.