Matthew Smith , Mar 29, 2000; 10:57 p.m.
Ask the manager. If he says no, there's nothing you can do. This fall, during the big hurricane in North Carolina a paper I was writing for wanted to photograph the local Wal-Mart helping people get ready for the storm and the long lines they were waiting at. The manager said no to several different people with cameras. It seemed to me, however, the Wal-Mart was doing a service, staying late to help people while undoubtedly they all had worried families at home that needed them, and the photo would have showed that.
I would recommend saying, if it's true, that you're a tourist and you want to take some pictures to show the folks back home what this local landmark is like. I wouldn't recommend having a "big fancy" camera." That is suspicious. And what ever you do don't take photos without asking for permission first. If you ask a lot of stores, one or two will let you.
I can't say I understand why stores do this, but I'm not sure I blame them either.