That has to be the worst quote in regards to music. Stravinsky claimed to be an inventor of music, yet supports idea theft. Imitation is the sincerest form of flattery, so if you imitate someone, you are either paying homage to them, or at least acknowledging them as your influence. Claiming others' works as your own is the worst thing you can do in music because it's arrogant.
Stravinsky was most liekly advocating stealing ideas like themes or passages, but not outright pieces. Zeppelin did that throughout their career, giving little or usually no credit, unless forced to do so, like acknowledging Anne Bredon for "Babe, I'm Gonna Leave You" after a lawsuit forced them to do so, in the 1980s.
You can idolize the band if you want. I could see that from their musicianship and performing qualities, but personally I refuse to do so. I respect creativity more than performances, and to be a legendary band, you should have that spark to write an amazing original piece.