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Building on the previous post, Singapore Airlines largely make their money on these services from the business class section (+ some last minute PE travel) and often sell PE in advance at economy prices to fill the plane. In fact it's often cheaper to purchase Singapore/New York return in PE on the non-stop services than to purchase economy on the single stop service via FRA that actually has an economy cabin.

No catch, other than a long non-stop flight. But have done it in both PE and business class cabins, as have many others, and it's certainly manageable. Plus for some a bucket list flight (EWR-SIN is the second longest non-stop flight currently operating, eclipsed by JFK-SIN which is 3 miles longer, also on the same type of Singapore Airlines aircraft). Until Qantas starts doing London/Sydney.