Probably texting each other "look at that family staring at us and shaking their heads." 
OP - you would have thought we were a horrible family this past weekend. We were out of town. We spent so much "together" time that we were ready for some down time. Dinner was our time to have some private space. It was the first time we could all sit down and check messages, and check in with life.
And hubby had to be on his phone for work. He is on call 24/7, even on vacation. If he didn't check his phone, he wouldn't be able to be with his family the other 23 hours of the day.
But...I would rather my kids check their e-mail at the table than be a nosy Gladys Kravitz and gossip about what the other tables are doing and how they don't meet your parenting standards.
Oh, and FWIW - dinner at the dining room table, which we do nightly even if it means having to do dinner at 9pm to accomodate schedules - no electronics allowed.
We even have discussions about being judgemental and how to avoid that. So, no problems you need to worry your little head over, thank you very much.