Being compelled to have lunch with colleagues every day sucks. Sometimes you are feeling cranky, want some fresh air, need to run errands, or have a hot date.
Not having the opportunity to lunch with colleagues also sucks. It provides a great opportunity for employees to get to know each other, make friends, and informally discuss company business.
Seems the onus is on the company to make lunch pleasant, and perhaps to steer newcomers into the middle of the crowd. After that, create the kind of environment where no one feels compelled to do anything, but employees want to eat with each other at least a lot of the time.