Grandmother stopped buying food?

Hey everyone. I'm a 20 year old male & live in a double block with my mom, and step father. My two uncles, grandfather & grandmother live on the opposite side (Long story about them living with their parents, They are pretty much two born losers with one being a drunk). It may sound heartless to say, but I've seen what they are in my 20 years of life & trust me it's nothing more than wasted oxygen that someone else can use. Thank God we are out of here in a month & away from these genetic failures. Anyways, the past year it seems like my grandmother has gradually stopped buying food more & more. Like if you look in the refridgerater right now, there's ketchup, mustard (the condiments) and maybe some cupcakes & desert cakes like those (Tasty Cakes). I don't know the reason for this. That thing used to be STOCKED with food for a large family. Even though I have my own money, my mom still feeds me because I'm still living at home; I guess it's a mothers' instinct to provide. Before anyone asks; no, I don't use my grandmother for food. I'm just very curious as to why she's stopped buying groceries. When we move out in a month or so's time, the family is having a meeting to decide what to do with my grandparents. They urinate themselves daily & cannot provide for themselves. My uncle goes to the store every week, but it seems he buys more food for himself than my grandparents with their money. It's been this way for YEARS, so trust me it's not going to change as long as she allows it. My grandmother is going to be 80 & still makes my uncles' beds, who are 47 & 51 in age. Now you see why I say they have should've been aborted before birth, they are complete wastes. Anyway, What is the main reason she has stopped buying food? Like I said, it was always plentiful in years prior. Thanks.