OK, as a food guy, I gotta put in my two cents worth and a little more, and forgive me preaching the gospel of food safety.
Just my observations, but food poisoning seems to be very common and most often occurs at home. How would I avoid it? Use a meat thermometer, and wash your hands, bulk produce, utensils, cutting boards, and counter tops. Keep a sink full of HOT soapy water. Never use a utensil on raw food and then on cooked food. Wash your hands after touching any raw food. Sounds like a lot, right? I'm here to tell you that it sure beats vomiting and diarhea and the "stomach bug" rarely is anything but food poisoning. Follow these easy steps or get sick, your choice.
When you go out, if you don't think it's right or the waitstaff touches the food, send it back. A refund won't keep you healthy, just send it back. Simple advice but nobody does it. Why not? Remember, it's your health and your money, too.
IMHO, it's not just the meat and the lettuce. There are other sources for contamination and problems, too. Do the fieldworkers have proper "facilities" or are the growers too cheap? Is there chemical or animal waste runoff from another farm? Has the food always been kept under safe conditions before you bought it? Did the store pull or recall the items ASAP or did they try to make a few extra bucks? This is why you get what you pay for most of the time and why the cheapest food isn't always a good buy. Again, only my opinions, but...
It might be that we get more prone to food borne illnesses because of being limited to the exposure of some bacterias or viruses, but I find that kind of far fetched and I don't want to test that theory on my family. There really are virsuses that can be food borne (that's one opinion about the recent Olive Garden problem). Why not try to avoid those, too, like we avoid measles, pneumonia, etc.?
Some problems might be caused by bacteria or contamination being drawn up into the food, so washing will probably do no good in those cases. Then why wash produce at all? You should watch the way some customers handle produce in a store. Did you really just see that woman pick her nose before she handled those tomatoes? Did that kid just sneeze into his hand before he grabbed those apples? When Dad changed that diaper did he really wash his hands well afterwards? And I'll bet you were just worried about the kid who stocked the lettuce. Also, there is no "five second rule." Sorry.
The easiest way to avoid getting sick is to to a little extra work that you should be doing anyway. Buy quality food even if it costs a bit more. Read the labels. Keep stuff clean. Use that meat thermometer. Wash your hands like you're obsessive/compulsive. You'll have a better chance of not driving the porcelain bus. But there are still a lot of guys out there who are too lazy to lift the seat before they piddle, so it's an uphill battle, but you just do what you can. Why, yes, you are right, it really is a scary world out there. The extra time it takes to safely choose and prepare your own food is a good way to stay healthy. Or you can trust the pimply kid who gets paid minimum wage to serve you food that was prepared safely. But I think it's the penny pincher who bought the cheap ingrediants for the whole chain that worries me more.
When you're out to eat, you're on your own. I don't like chain restaurants too much simply because I find them boring and that they have no local flavor. IMHO, I think there is a bigger chance of getting food poisoning at a chain, but YMMV. Local places are more interesting to me, but also, you can find out where the food came from easier if there is a problem. Also, locals usually try harder to keep customers.
Does it work? Well, it does for us. My family has had food poisoning about twice in the past five years or more -- both from restaurants where we probably should have known better. Everybody screws up once in a while, but the effort to cook good food properly is worth it, at least for my family.
That concludes today's sermon.