Munchies:
Only if you gain slowly and up to a certain point. What that point is depends on how you carry your weight, but if you gain past that, they will notice.
But why must you hide it?
EndlessGain:
As I said, just feels awkward eating too much around people who aren’t into it.
You didn't, but I get you.
Before my partner decided to loose some weight, he used to "pre-game" his meals. Basically, he'd eat something by himself before he'd join others for meals.
That said, most people aren't going to think you're gaining on purpose. They'll think you really like food and haven't noticed or don't care about gaining weight.
My partner used to be about 200 lbs before he realized he had a fat fetish. He fattened up to 400 lbs before he met me. Then I pushed him up to 500 before we stopped.
No one assumed he had a fetish. In fact, since I've always encouraged him to be active and cut back on junk food, his friends and family assume that he decided to lose weight for my sake.
We joke about it all the time.