I didn't read the OP, but this is clear from our my own privileged knowledge:
You are most likely to get sick at restaurants from the ice, ice tea, and uncooked vegetables.
Now to the subject line, the problem with it is that toilet water in most folks' places in America is rather clean, in fact is it "cleaner" than most other places in the home.
If you flush your toilet regularly, especially after every bowel movement and clean it occasionally, even the colonizing bacteria you get while unsavory looking are relatively benign.
In short, you can pretty much replace restaurant ice in the subject line with anything else and still be correct.
To the dangers of ice, iced tea, and uncooked vegetables, really you are only at risk if you are very young child, elderly, or somehow immunocompromised.
And, this goes against Maria's and marc's general take on food. If you want a safe food supply chain capable of supporting the behaviors of people living in America something exactly like Taco Bell and McDonald's is the answer.
You are highly unlikely to get sick at either one, especially since they've changed their method of ice tea delivery (not made on site) and ice delivery (as little cross contamination as possible with other surfaces).
Highly processed food is very safe food. Raw food isn't, relatively speaking.