I've gone into Outback Steakhouse at 11am when they open and sat at a large table in the bar area. Almost no one is in the bar at 11am. I can work, make calls, etc. and have a great lunch all at the same time. I also ask first in case they have a party coming in so I'm not in the way. I've never been told no.

I've done the same thing at IHOP. I found a table all the way in the back that had an electrical outlet under the table. I plugged up, filled my gut, drank from their endless pot of coffee and got some work done there too.