The egg is commonly considered a non-vegetarian food, but there are numerous facts that do not entirely support this comment. If we go by the definition that those who eat flesh are non-vegetarians, the egg is indeed vegetarian as it has no flesh or life.

But eggs come from chicken!
Eggs come from chicken, but they are not received by killing a chicken like caviar or fish eggs are obtained. Not every product that comes out of an animal is non-vegetarian, the best example being milk.

Egg white is the purest

Eggs include three parts- the shell, the albumen (white) and the yolk. The egg white is a suspension of the protein albumen in water. It carries no animal cell. Hence, egg whites are vegetarian and all products containing egg whites are, technically, vegetarian.

Yolk too is mostly veg, but....

Most of the yolk is a suspension of fat, cholesterol and protein in water, but since the gamete cells cannot completely be demarcated from the yellow portion, the yolk is non-veg.

Eggs could have given chicks
Maximum eggs available in the market are unfertilized ones, so there is hardly a possibility that a chick could have come out of it, had you spared that egg!