Age discrimination generally happens as a result of the fact that younger people are less experienced in the world and so will need some guidance. If you were never told that smoking would destroy your lungs and kill you, just that "It feels good man," would you do it? Probably. However, some people take this to far and abuse their power over younger people. Is this kind of discrimination justified? NO.
Age discrimination can apply to several levels of age, but I will refer to two. The first being below 18. If a person is under the age of 18, almost all decision making is placed in the hands of their parent or guardian. This is because those that are below 18 typically cannot make responsiblie decisions for themselves. This also applies to people in the elderly population. The argument is a little different, since the elderly are thought to be able to make these decisions, but for whatever reason, society thinks they shouldn't be bothered with such decisions like health care or where to live.
So to those who think age discrimination is not justified, then screw it. Wish I could go back in time to when I was 14, to have intercourse with older people, drink alcohol, smoke tobacco, fight a war, go to a strip club, drive, and vote. PEOPLE WHO DISCRIMINATE AGAINST AGE MAKE ME SICK! >:[
I believe that age discrimination is justified. While it is never a good thing to discriminate against somebody due to age, race, etc, I think that some workplaces have to critically judge somebody for their age. A company cannot risk hiring somebody that is too hold to do the job properly.
I do not think that age discrimination is justified. You should not be restricted from doing things just because of your age, or assumed unfit to be able to carry out tasks because of it. This is ridiculous, and should be done away with unless the person is unfit to do so.
Age discrimination is not justified. Discriminating against a person based on their age is the same as discrimination based on color or sex. People of a certain age can be just as productive as people of a younger age, being older doesn't necessarily disqualify a person from being a productive worker.