Brian made a compelling argument:
Suppose they offered a "veggie-less day" where every single thing offered had meat in it. That would probably upset the vegetarians. So, eliminating meat for us carnivores is like having a day without an entree. Limiting an entire class of food from the menu is especially pertinent for people who are on restricted diets who have to limit their carb intake, or who have wheat, gluten, soy, or peanut allergies.Although I don't agree that it is quite the same (but that argument is for a different time), I see his point.
Regardless, the more I thought about it, what I see is that the real issue is that Bowdoin's goal was to encourage students to make what they see as a positive lifestyle change. It just seems as though they didn't really think their plan through using any sort of social/behavioral change model. Although there's research to support it (too lazy to look it up), it's really common knowledge that most people (especially teenagers and college students) don't like to be told what's good for them or what to do. If anything, forcing the issue of Meatless Mondays probably backfired for a significant part of the student population, because they will view it resentfully as "stupid" because they feel it was forced on them.
It might have worked better to make Meatless Monday enticing, but not mandatory...have some eye-catching, compelling publicity in the dining halls. Offer an incentive to eat Meatless on Monday. On Mondays, serve your very most delicious vegetarian dish, and your crappiest meat dish. This way, you get students to think about it and make a conscious choice if and when they are ready to. You also give them the option to "try it out" if they want to, without feeling forced.
Truthfully, going one day a week without meat is not hard. At all. It takes a little bit of planning because you're designating a particular day, but the same would be true if we designated Fish Friday (which some of y'all do) or Pancake Sunday. Kevin and I often find ourselves eating several meatless meals in a week, just because that's what we like to eat. Mac and cheese, spaghetti, many Indian dishes. But I totally get that if it's shoved down your throat (literally, I guess), you're going to want to fight it.