Why is it legal to drive while eating a burger or drinking coffee, but not while talking on a mobile phone?

There is evidence that while we are using a mobile phone when we are driving, we increase the motorist's likelihood of having an accident. Government led to a ban of using mobile phones in cars. The only way that you can talk with somebody on your telephone is to have a headset that allows hands-free use. Yet drivers may legally engage in other activities that appear to be at least as hazardous- eating fast food, drinking coffee, changing CD/music, even using your cosmetics. But why is using a mobile phone not legal, but putting on make-up is allowed ?

It is possible that mobile phones are more distracting than other activities. A driver who becomes angry during their ride is much more inattentive than somebody who eats a burger. It may cause an accident. Yet talking to another passenger is legal, isn't that the same as talking to somebody using a mobile phone? However passengers may be able tell when traffic conditions dictate interrupting the conversation. Since we can use our mobile phones, but only with headsets, this solution is insufficient.

On the other hand if government would decide to put a ban on burgers and drinks in cars, there would probably be a big fall in demand for these products, because most of them are eaten/drunk in car.

If it is concerns headsets they are profitable for everybody. There is a high demand for this product, because everyone who have a phone has to have this product, therefore they have to buy it. It is also very useful for drivers, because they have both hands free, which makes it less dangerous to talk while they are driving a car.