Bennigan's is notorious for poor HR and people practices. Unfortunate for the employees, but good that they have the chance to get themselves into a stronger, more people-focused company. There are any number of reasons why you don't tell your staff you're closing, but there are better ways to handle it once the decision has been made.
I won't try to convince anyone of the virtues of corporate restaurants, but having been in the industry for 13 years I can tell you that the only times I haven't had full medical, dental, vision, and 401k in my adult life were when I was working for mom and pop restaurants. Quality of product was outstanding, quality of employee benefits was not. There are some great employee-focused companies out there, but they're usually the biggest and most often-picked on for whatever anti-capitalist reasons, despite often offering strong benefits packages.
Of course, they're big because people like working for them.