do you mistreat them even more because they're bbws?
Of course not! I would never mistreat any woman that wasn't related to me.
Do they like feeding their men comfort food?
Do you actually have to hold their flab/legs to the side during intercourse?
Do they really only go after skinny dudes?
The flab holding is a thing that happens in adult films and pornos. In real life, it's mostly heavy breathing and scratching.
BBWs mostly go after skinny/average build guys that look active. If you are dating, not just smashing, expect to be more of a personal assistant that a BF. It's a lot of running to the store to get more food and picking up things that she can't.

in the bbw's private fantasies/daydreams..
does the man of her dreams want her as she is ??
or does she imagine herself transformed and then the man of her dreams appears??
Every big woman dreams of being smaller, which is why many have an attitude about life in general. When they finish their meditations over a bag of doritos, they long for a man that will accept them for who they are, but also tactfully inspire her to get into working out and eating more.
Most chubby chicks won't admit it, but they, like all women, love the feeling of losing weight and validating magazines and physicians. I fukked 10 pounds off a BBW in 3 weeks and she loved me for it. I had to let her go because I was tired of cookie crumbs in the bed.