The Star Tribune had an article today about more restaurant diners splitting meals, attributing it to cost savings. See "Dining out? Split portions gain acceptance" by Lauren Shepherd for the Associated Press.
Could it also be because so many restaurants serve such large portions that few people really want to eat it all? If you're eating in your home town, you can always ask for "a box". But if you're traveling, a box is only useful if you have access to a microwave.
I often find myself looking for what is the smallest serving, stuffing myself, or asking for a box. Sometimes I don't even go out because I know I will be served too much!
I don't think it's just the economy. I wrote about split portions in 2006. See
"Why pick on McDonald's and Wal-Mart?"