Back in the heydays when airlines were doing better, I 'ordered' a cake for a friend who was travelling with me on his birthday... on Air Canada in economy. And yes, it was provided, along with 2 FAs who couldn't for the likes of themselves sing Happy Birthday properly. They even came round with 2 glasses of champagne!

Ahh.. those were the days.

But I think SQ , on odd occasions and for 'special' people still would do it.