I'm in the, shall we say, older category, and I guess I'm not quite sure what qualifies as graffiti and what might be considered street art or graphic art. When I see obvious gang markings on signs and other objects, I derive no specific meaning from the markings. When I see beautiful artwork on the sides of buildings or wherever, I am moved to appreciation. They are probably both graffiti because they are both technically defacing public property; however, I do not put them in the same category otherwise.
It tends to be associated with younger people, but let's remember graffiti is by no means a new invention. "Kilroy was here" was painted across western Europe by American troops and graffiti was a protest vehicle in Europe, North America and Latin America from the 1960s to the modern day, so it stands to reason there are graffiti artists in their 70s and 80s now who, while not still practicing the act/art of graffiti, remember its value in their day.
While it appeals more to the younger generation, I think, there are several of us *ahem* older people who certainly see the beauty in some of it. Where we may differ is in content. I think young people tend to push the envelope when it comes to sexual/gang type content which some of we baby boomers might find offensive. But I actually have a graffitti wall in my kitchen that I encourage young people to contribute to when they visit. It gives me a beautiful remembrance of their visit and livens up the area.
I often find myself giving long looks at various forms of graffiti, and some of it is worth more than just an admiring glance. However, I never have the urge to contribute myself, and I think it is far more appealing to the younger generation. Graffiti in public places is usually an illegal form of vandalism, and most older people know better than to risk an arrest over such a matter.
Graffiti has been around since ancient Rome, and probably long before that. There seems to be a universal impulse among humans to mark territory somehow. Roman graffiti seems to fall into two categories -general messages that can be understood by almost any viewer, and insider-type statements. I think that is still true in the modern world; while I may realize that a certain piece of graffiti is a gang tag, it's significance beyond mere recognition is lost on me, but the same work may convey a lot of information to an insider.
Graffiti is significant to all of us at some level because we are exposed to it whether we want to be or not. Just like advertising and art, its value is in the eye and mind of the beholder. Some of it is quite beautiful, some is ugly, and some of it is just...there. I, as a middle aged viewer, may or may not appreciate the nuances of a specific piece of graffiti, but that does not prevent me from making an aesthetic judgement of it in my own mind. However my appreciation of it would probably be enhanced, or at least informed, by further knowledge of the work's cultural context; this however is true of any art. Do I like all graffiti? No. But I don't like all Picassos either.
I agree with the previous post - to some extent, the answer depends on what you are defining as graffiti. If you are referring to messages spray painted on bridge overpass structures or train cars, the content of the messages will be relevant to a wide variety of people connected by the topic of the message, not the age of the reader. If you are referring to signs or symbols indicating territorial boundaries of street gangs, you are looking at graffiti that will be most meaningful to the probably youthful members of the gangs present in the area. Refer to this link (http://en.wikipedia.org/wiki/Banksy) for information about a recognized graffiti artist in Bristol, England whose work is widespread, recognized, imitated (which some would say is the highest form of compliment), and controversial in some circles regardless of age.
Though it may be true that there are more people in younger generations that are interested in or have some knowledge of graffiti, it has been around long enough that there are certainly older people who are familiar with it and find it interesting. Of course for graffiti artists, there is often a desire to project a certain kind of message and so their audience may be limited to people that know their tag, or it might be intended for everyone that sees a larger message or even picture that they've placed in a certain location.
In some ways the answer also depends on the definition of graffiti. If you consider all of its forms, people may in fact relate to it but just don't consider it graffiti.
Graffiti is relevant to all types of people, whether they are an older or younger generation. My proof is that graffiti has been around for many ages now and it is widely accepted because, as research shows, graffiti is a form a spray paint. In this day and age, you use a spray can of paint to make graffiti. In the ancient days, you crushed berries, leaves, rocks, or anything that makes pigment and you blow it through a hole in a stick or through your mouth to make designs or drawings on caves.