As for the phone debate, I always bring my phone with me to the parks. Mainly because I don't wear a watch

.
Cell service is spotty at best though, and I know several international travelers don't use any service on their phones due to huge international charges (and this includes Canada). It's certainly an interesting proposal though.
LOL! There are more restaurants at Disney that begin with C, than any other letter, I believe. Anyway, my experience has been quite the opposite of yours. I've been to Chef Mickey's and Crystal Palace multiple times (and Coral Reef once) and the only empty tables I've ever seen were when we had an opening time ADR (or when the table was being cleared). BUT, my vacations are typically either during President's Week or August and the parks are far from empty. So, perhaps time of year has a lot to do with it.
Don't forget Captain Cooks, Contempo Cafe, Captain's Grille, CRT, Cap'n Jack's, Chef's de France, Columbia Harbor House, Cosmic Rays, Cafe Rix, and Citrico's

(And that's leaving out the named snack stands

) (Yes, I looked them all up between Cap'n Jack's and Citricos)
This brings up something interesting. These people who are seeing all but their table empty (ok, that's exaggeration), are you going during slower park times? Maybe the two are inter-related, more CMs during busy times = more tables available = less empty tables. Fewer CMs during slow times = fewer tables available = more empty tables.
For those that are harping on "5 or 6 sick CMs" are missing the point. We're talking about initial scheduling 6 months out to only have an 80% capacity based on staff (for example). Just because all the ADRs are gone, does NOT mean that every table in the place is booked. It means every table they're expecting to be available based on planned staff levels is booked.
And there are far more than one host/hostess at most Disney restaurants. One or two checking in, then 3 or 4 (at least) seating people. Those are the hosts/hostesses. Losing one can mean a delay in seating, driving down the working capacity.
Buffets also require a set amount of cooks and servers per table, and due to all the different foods prepared, I'd actually think that more cooks would be needed for these restaurants. Sure, they don't cook to order, but with more tables means more of the various pans being emptied faster.