You clearly should be ashamed, missy!
My guess is that, if they were at Sam’s Club, they were probably 40 or 50 lb bags. But the point is, nitpicking your advice, like Contrapuntal, was rather irritating.
I ate meat maybe once a week at most when I was a broke-ass student (and in the couple of years of minimum-wage jobs that followed). You’d be surprised how easy it can be, as long as you make sure to shop in the right places.
Try to shop outside the big supermarkets. I’ve saved tons by sticking to ethnic markets, independent greengrocers and fruit stands, and warehouse stores like Costco.
Aside from the rice and beans that have already been mentioned, there are dozens of other cheap meat-free options.
My usual suspects:
Lentil Soup (Middle Eastern style with red lentils, or European style with brown lentils)
Vegetarian Pastas (lasagna is easy to make ahead in large quantity, and freezes beautifully)
High-Protein Salads (w/ lots of chickpeas, beans or lentils)
Frittatas (stir in cottage cheese for extra protein)
Stir Fried Veggies on Rice (w/ or w/o tofu)
Homemade Noodle Soups (dried shiitake caps from an Asian grocer can be used as the base for a delicious broth… they’re a bit pricey, but provide lots of bang for your buck)
BTW, this recipe for chickpea and sweet potato kofkas from Mollie Katzen makes great veggie-friendly burgers. Tastier and cheaper than store-bought, too. (Mollie’s site has lots of other great veggie-friendly recipes, many of which are quite affordable)
Thanks everyone for the continuing advice. We actually have made lasagne recently and it kept long past the day we were going to throw it out.
I’ve got the beginnings of a grocery list together… the cupboards are almost empty so tonight will be a shopping trip. If we can keep the bill under $75 I’ll be happy.
As for the bag of rice, it’s not a big deal whether it serves 10 or 100,000. 
Suffice it to say it’s a great deal. However - TMI warning: I’m told they sometimes have moth larvae in them, and while it may be impossible to completely remove insect eggs/larvae from one’s diet, we’re thinking a small bag will avoid giving them enough time to grow into adults.
On a related note, has anyone else had where you’ve just eaten and feel hungry again 5 minutes later? Might we not be getting enough of some vitamin?
umop, if you’ve got a freezer, store your rice there. We’ve got a flour moth problem, so most of our grains and flour get stored in non-moth friendly places.
Also, consider using a pressure cooker to cook all types of delicious meals. You get more bang for your buck electricity-wise, since cooking times are a fraction of those for conventional cooking methods and, in my experience, most pressure cooked dishes come out tasting particularly flavorful and tender.