My store tried to do this before two years ago because a team member was on his lunch and used profanity in food ave and got a complaint, but it didn't last long because everyone was upset with that ruling.
Now my STL announced at last nights huddle the enforcement, in which he stated it was because: "The guests should have the seats available to them." But, I have never seen the half the tables occupied at any time of the three years I've been at the store. I double checked the Team Member Handbook, and under "Rest Breaks and meal periods," it says: "Please take your break in an area where guests won't disturb your break, such as the team members breakroom." To me that doesn't sound like a requirement but a suggestion. With the way that sentence is, it sounds like I can't even do any shopping on my lunch break. If I am off the clock, I do not see how they can tell me where to be as long as I am not a distraction to other team members or a nuisance to any guest(s).
Everyone in my store is not happy about this policy being informed, but it probably won't get enforced since the ETLs/STL are too lazy to see anything through. The ironic thing is, I never am at starbucks/food ave but i think the policy is just plain wrong.