They're designed so that, if necessary, they can be operated by a single employee. That's why they're so tightly cramped around the grill: so that someone can cook and still keep an eye on a table.
This is also what makes it really easy to get attached to your local Waffle House: the staff make the place what it is.
Waffle house is cramped, brightly lit with harsh fluorescent light, and nothing but hard surfaces. A few drunk people talking is enough to fill the entire restaurant including the exposed kitchen with sound. If they start throwing anything it quickly hits everyone in the restaurant including the line cooks. I've seen probably four people vomit all over the place in a waffle house. I can't say I've seen anything quite the same in the dennys, usually its truckers and the elderly there not people showing up after last call at the bars.