I don't necessarily agree that being vegetarian/vegan is inherently more expensive than being an omnivore, but I'd like to point out the meat industry receives a lot of government subsidies (at least in the USA) and that helps keep costs down. Vegetarian/Vegan options would be more affordable if they got the same government subsidies as the beef industry. Sure, things like corn/wheat/soybeans receive decent subsidies, but most of that is for feeding, you guessed it, livestock.