As is often the case when a deaf person sets their mind to a particular task, that person becomes oblivious to the world. This is because
This condition is even more acute when the deaf person (particularly a hearing-aid wearer) is eating. This is because all the hearing aid wearer can hear is the sound of their jaw-bone rattling around underneath their ears. When you bear in mind that a lot of sound is transmitted through the bones (lightly tap yourself on the head and notice how loud it sounds), it is hardly surprising that eating turns out to be a noisy exercise for someone who doesn’t hear much sound — you have to remember that deaf people can often hear these bone-transmitted inner-head sounds just as loudly as hearing people can; it is only sound arriving by the ears which is diminished.
In a noisy environment it usually turns out that the general hubbub of conversation averages out to a drone at about the same pitch as the rattling jaw bone. Now, not only does a deaf person have to put up with the sound of eating, but any sound that does come through the ears is camouflaged. Few deaf people will be able to cope in a noisy eating environment (signers would have a better chance, but they have their hands full…)