The Lunacy of Valuations

To give you more insight into IPOs, the lunacy of valuations, and the insanity.
Shake Shack IPOed today and is trading at an eye-popping price-to-earnings ratio of about 325, with each restaurant valued at about $27 million.
1.6 b market cap.
Insanity.
Hence why a Spotify IPO would have zero problem with a 10 – 15 billion dollar valuation.