Clothing is still a popular gift for any occassion. People who give clothes often know the person they are giving them too, often intimately. This makes it a pleasure for the giver to see a gift appreciated, and actual usage is the best method of appreciation. Clothes are, by function, the more readily observable ones. Also, depending on quality and usage, clothes are a lasting gift.
Variety assures a good selection, appropriate for the season or person the gift is intended for. Sports wear, like NFL jerseys, is always a good option, specially for youth, since they are appropriate wear for almost all casual affairs and they never go out of style. While polo shirts are a bit more formal, mainly because of the collar and style, although still considered casual. Trendy apparel is also a good gift since they are almost always up to date fashion wise, and makers like Ed Hardy, sees to that well.