I always leave a small tip when i go to CICI's for the people who clear off the table. they clear the dishes I have finished usually when I go for 2nds or after I get back.
No, they don't refill sodas, etc... but they do work hard, at a job I wouldn't want to do.
I went to the original one near Comfort Inn once and left $2.00 on the table. The lady ran after me and said "you left some money on the table". when I told her it was for her she thanked me a few times before I got out the door, I guess she doesn't get many tips, which is a shame, she was right on top of everything.
I can't eat pizza anymore so no more CICI's for me, and I will miss it. It wasn't the best, but when I went to WDW alone it was a nice place to stop after hitting the outlets.