I have noticed a strange lack of expansion content for the Yo-kai Watch games considering there are two Yo-kai with canon expansion related powers. Let's educate the people of Yo-kai Watch's fetish potential.
First there is the patron Yo-kai of stuffing Hungramps.
With the ability to make people feel hungry even when they're stuffed to the gills. Hungramps actually made the main character Nate and his mother get large balloon bellies on the animated series.
Meganyan the next yo-kai is from the second game and has actual expansion powers.
Meganyan is an alternate form of the yo-kai Hovernyan with magical backup? and he can use his magical breath to make things bigger because he's bigger I guess. Once again the main character Nate is affected by this yo-kai having his head grown to comically huge proportions for a quick gag.
So why do you think these two haven't been utilized more often to cause expansion related mischief? Is it just no one in the community knows or cares about them or Yo-kai Watch I hope not, and hopefully this will shed some more focus on the fun characters.
I would consider myself as a gamer, and I've never heard of this, which maybe answers your question somewhat. We do see a lot of posts along the lines of 'why isn't there more [insert niche TV show / game] based inflation, and the majority of the community I think aren't even too bothered about inflation involving characters from other things anyway.
As with everything, be the change you wish to see. If you think there isn't enough of something then create it.