Photo: VirtualErnThe answer is:
People buy less food and subsequently eat less and throw away less. For the customer, it’s good for the budget and the waistline; for the cafeteria (and the environment), it substantially cuts down on waste. Sounds like a win-win situation, unless you are the party who profits most from selling a high volume of food. Here, from an article in Restaurants and Institutions, are some details:
Foodservice managers find that when trays are eliminated from all-you-can-eat dining halls, diners take less food and therefore waste less. In a study released this summer, Philadelphia-based Aramark Higher Education reported that schools saw a 25 percent to 30 percent drop in food waste per person when trays were removed.
In addition, the move cuts back on overhead, because there are no purchase or ongoing replacement costs for trays, says Tom Post, president of campus dining for Gaithersburg, Md.-based Sodexo, which manages foodservice programs on more than 600 campuses. Many Sodexo campus accounts already have retired their trays.
Hat tip goes to Josh Friedland, who blogged about this at The Food Section. For further reading, see earlier posts on the Dutch university cafeteria that’s set up as a behavioral lab and the notion of whether a rise in plumbing facilities encourages a rise in food consumption.
I also wonder if trayless cafeterias might see a spike in shoplifting. It might begin accidentally. Since roughly 83 percent* of college undergrads wear sweat pants to breakfast, I can see them using a big, baggy pocket to hold the orange juice or breakfast burrito that they can’t comfortably carry, only to discover they’ve gone past the checkout without paying for it, thus realizing how easy it would be to do it again and again. This would of course be hard to do with scrambled eggs or a salad.
*Made-up statistic.

“This would of course be hard to do with scrambled eggs or a salad.”
From experience (not shoplifting, but carrying it to class after purchasing it)… not as hard as you might think.
I certainly hope that they don’t get rid of the trays at Willard Straight Hall. How would freshman slide down the hill?
At the University of Maryland we had an a la carte system, so I don’t imagine eliminating trays would help as much, since the main deterrent on over-consumption was the limited number of dining hall “points” (expressed in dollar amounts) you had available each semester.
One significant factor, however, was that freshmen and sophomores (the main dining services customers) would frequently steal the trays for use as makeshift sleds when it snowed. They weren’t very useful as sleds, but it was the best we could usually do.
Man I hated Aramark. They would require us to buy 14 meals a week at $7-9 each. They would then get all that money upfront. How much could it cost to make that junk pizza and coke? I imagine they were turning at least $3 in profit a meal. The real kicker was meals don’t roll over so they just pocketed what people didn’t eat which was often 100-150 meals a year. This gave them horrible incentive to keep the food quality and variety up. After a few weeks they would be on a rotation of a few things and you would be forced to forgo your prepaid meals to eat anything different. We were able to get them back a little bit senior year. We had two accounts; a meal account and a al la carte account of cash. The cash was refunded upon graduation. We maxed out our miles credit cards the week before graduation and then immediately paid off the balance when we got the check from Aramark. We ended up 10-15k miles and it probably cost Aramark around $300 to $400. I don’t think I would have done it if Aramark hadn’t treated us the same as the prisoners they serve.
I worked at Santa Rosa Hewlett Packard, where my friend and I saw a technician or assembler look like she was going to pay for the bagel in the cafeteria line, but then slipped it into her pocket and walked out so fast I couldn’t think to shout. She would also dive into the newspaper dispenser as someone was taking a paid-for paper, and quickly snatch out another paper.
HP was too politically correct to require people to speak English, or to assume anyone was stealing.
My friend and I nicknamed her ‘the bagel-snatcher”.
Sodexho runs the food at my campus. Every Thursday, they take away our lunch trays. This obviously isn’t very popular with the students who (as #6 mentioned) are left with the burden of transporting plates, silverware, etc. while carrying books and bags as well.
The response? As students, we offer Sodexho a choice. If they provide us with trays, we’re happy. If they reduce trays to prevent waste, every single student leaves their dishes. Sodexho workers then end up bussing tables. It’ll be interesting to see who caves first.
Without cafeteria trays, what are you supposed to steal and use as sleds the first time it snows? Desktops? Whiteboards?
WSU Pullman went a la carte. Pay for each dish you buy. Since I eat less than a college boy, this is the best system: don’t punish light eaters via the health-insurance-premium type of scam.
Their few vegetarian dishes were drowning in cheese, which the college students liked best. The server who smirked at me for ordering rice had a face that looked like a land mine.
So the a la carte may have been the only really good thing about them.