Different scenario. Katakuri had his merienda because he thought his task had already completed. He already buried Luffy with mochi and won his 1st round.
Here, King knows situation is dire, that he needs to stop everyone from reaching the rooftop where Kaido is.
Katakuri was also viewed as perfect brother by his siblings, his Merienda was supposed to show his secret hidden beneath his scarf. King isn't viewed as perfect by his crewmates, Queen shittalked him and F6 were seen annoyed after knowing the one summoned them wasn't Kaido, but King using his name.
It's because the story haven't reached King's floor yet. Simple as that.
Who's Who makes more sense among the 2. His womanizer personality was seen already when he had fun with his 2 catgirl crewmates, so him having fun with the protistutes aren't something really new. While King is never portrayed as womanizer at all.
Thread won't age well anyway according to the old record of Daifuku the former SC, roided Ichiji, Judge's son vs Daifuku, etc etc. So
@Chrono thinking King will have a Merienda is kinda confirming the opposite.