red Robin has a rewards program where you get every 10th item free. combined with bottomless fries and drinks with an entree, there's a way to spend less than 100 dollars a month on food and be massive huge at the same time. the process consists of three day cycles:

day 1 - red Robin day
get to red Robin right when they open (will vary but usually around 9am). immediately order the plain burger with bottomless fries and drink ($10). now you can spend the rest of the day (approx . 12 hrs) in red Robin doing remote work, playing video games, etc. while sustaining yourself off fries and soda. make sure to go with a high calorie soda for best effects. you can usually squeeze in up to an hour after the official close time and berate a server to give you one last order of fries.

day 2 - strength training
on this day you want to build up as much muscle as possible while wasting few calories. find a heavy weight (doesn't need to be at a gym since that adds to the cost) and focus on strengthening exercises for the entire day. you can take small cardio breaks for health reasons. most important thing is to NOT EAT on this day since you'll get all the nutrients you need at red Robin.

day 3: day of hygiene and rest.
you'll want to conserve energy as much as you can on day 3 since you'll be pretty tired from the lack of food (don't eat on this day either). make sure to clean yourself too since you'll be sweating pretty heavily on day 1 and 2. laying in the bath for around 6 hrs will help you conserve calories while also washing your body. you'll start to smell pretty bad because of the red Robin diet and strength exercises. use a little bit of soap in your bath since red Robin will use your smell as an excuse to kick you out if they get the chance.
if it's your 10th red Robin day you can get a free meal with their rewards program. get a big meal with lots of the micronutrients that's you won't get from the plain burger, fries, and soda.

if you did everything right you'll have just enough energy the next morning to get yourself to red Robin and begin the cycle again!
overall you'll only spend about 100 dollars on food a month, you'll bulk up and get massive, and you get free wifi from the red Robin