From my experience, the whole feederism thing is mainly developed from your family. It's pretty easy to point out that a chubby chaser has a fat parent or a fat family member that influenced their love for fat. It's something you grow up with and becomes normalised. It's normal for your mom to be fat, so you will probably copy that in your adult life. Plus if you have a fat parent, chances are the other one isn't helping them stay fit.
For example, my mom is the huge one, and gives a lot of importance to food and preparing it, so naturaly i like fatties and consider feeding them close to a love language. It's how i show i love them.
On the other hand i am on the spectrum and i do think a fat belly is easily the best stress toy to have around. I am simply dependent to having a huge chick, I have not tried living more than a few weeks without a huge girl for 3-4 years.
Another example is my actual gf. Huge porker, my first really dedicated feedee. She gains like she breathes. Almost 300 pounds, the biggest i ever had, (or seen) around here. Her grandparents always spoiled her rotten with so much food from an early age, she inevitably made a loving connection with food and stuffing excesively. But her mom (even if she is a bit chunky and probably the catalyst for the fatty gene in my gf) hates with a burning passion fatness, and tried all she could to prevent my gf's inevitable balooning. So, she started eating in secret and binging, forming a taboo and risque side to eating, so it became something she deeply enjoyed eroticaly in secret. (She gets very wet when i stuff her)
All this text just to point out that her little sister goes on the same path. She is smaller but started to get chunky the same way, has a bf who likes her like that and started talking with my gf about gaining and liking the fatness.
So I consider this to be heritable, just thinking about the posibility of me having kids with my gf, they will grow up with a huge mom who eats all day from pops hand and moans a bit. I think they will grow up to love fats too.