Why not Wynaut?

[Almonds]

Excluding Gen 1, every pokemon game had an egg given by NPCs, and they were featured in the anime. Most notably Misty's Togepi, and Brock's Happiny.

But in Gen3, there's a woman who gives you a Wynaut egg, but strangely, Wynaut weren't featured much in the anime. Instead, May and Ash got eggs that are not even Gen3 pokemon the moment they hatch.

Why did they not feature Wynaut?

 

[Kakuna Matata]

Wynaut was featured. It was even one of the 'Mons that we got a preview of back in Johto.

 

[Trainer Yusuf]

I assume that might be because Wynaut had already gotten enough showcasing for early Ruby/Sapphire promotion, both within his own short and as a recurring mon in Johto, albeit briefly. And when Ruby/Sapphire early promotion was over, his promotion in general was ended, and they probably thought there isn't further need to showcase it anymore. There are varios mons that get tons of merchandise or promotion but not much appearances, even if they are in the cast, such as Emolga, Pachirisu and Maggyo(seriously); or ones that get so much merchandise and brief appearances, like Kumasyun or Cherrim are not in the cast.

 

[Iteru]

What what a Wynaut be able to do on the cast that Wobbuffet hadn't previously showcased? I think that's what they had in mind.

Even then there have been more eggs like this. The egg in Crystal with the random baby Pokémon and Riolu from DPPt. Oddly Happiny and Togepi have gone on to be eggs in multiple games. I doubt we'll see anyone getting a Larvesta egg either.