Living with them is so unfair.

So I live with my parents for now as my husband got out of the military and is transitioning into a really good job. He starts feb 12th. So I have 2 older brothers that also live here and 2 younger siblings. So there's a lot of us at the house. All of the older kids pay rent. (Very small amount very appreciative of that) but ever since we moved in I noticed one of my older brothers haven't paid rent in over a year. I get it's none of my business and I let it go because if that's what my mom wants to do and let him just live off her when he's 28 years old then fine. (I am 20 and my husband is 22 my other older brother is 21) so my husband pays rent for us and my 21 yo brother also pays rent. My 28 year old brother has a gluten and lactose problem so my mom ALWAYS buys him special food and he makes sure nobody touches it EVEN THOUGH he doesn't pay for anything. Ok fast forward to today. I was having. A normal convo with my dad and my hubby said he'll get the rent for him and my mom is on the phone and she says "Oh btw the rent is being raised and also we need grocery money on top of that" ok I wouldn't be mad or upset if first of all she doesn't tell us THE DAY WERE SUPPOSED TO PAY and second the 28yo still doesn't pay shit and he works. My husband doesn't start working until the 12th and we have been living off our savings until then. I just think it's so unfair that he gets by and doesn't pa shit but now we're basically paying for the extra shit that he needs because we're paying even more. If it was fair and everyone paid every month and everyone bought their own food then I would be like ok I understand that's fair but it's not at all.

Whenever I bring it up to my mom she just says "well that's none of your business" BUT IT IS because now I'm paying extra because this grown ass man can't pay for anything but games!!! Freaking games. I can't stand it. Am I being irrational? Or do I have a reason to be upset? I'm pregnant so I am crying from how angry I am I'm tired of taking care of a grown ass man when he doesn't even help around the house at all. I clean up after everyone. Ok now I've just gone off topic lol. But if you read it this far thank you.