All the other girls have given great advice, but here's my take;
If I'm at the table eating then the kids are more likely to be happy to sit in their appropriate spots to sit and eat too, but sometimes I don''t feel like that and I like to graze or sit outside, or even sit on the floor with the kids. As long as we eat together if that's what I want, does it really matter where they eat?
While I do generally agree with you bubno3 about the tantrums, sometimes avoiding them at all is much more productive.