Hehehe,
FIRSTLY - Fetish is something inanimate or a part of the body that is non-sexual that causes arousal or sexual excitement.
So people with fetishes that are "big dick" "big boobs" "big balls" are NOT fetishes. You just enjoy/like/get aroused by those parts...
As a psychologist, I have to correct you on your definition of the word "fetish."
A (sexual) fetish is
a sexual attraction to objects, parts of the body, situations, or acts not conventionally viewed as being sexual in nature to the exclusion of the sexual partner (if any).
The key feature is that last part. Many men are sexually aroused by breasts, for instance, but a breast fetishist is turned on only by the breasts, and pays little or no attention to the woman they're attached to. In fact, she can often be an annoyance when he is getting off on them. The same is true of someone who has a fetish for large penises, a hairy chest, nipple play, or even buildings and cars (
objectophilia).
Many people with no education in psychology have a difficult time understanding that "abnormal" behaviors are always "normal" behaviors that are expressed in an abnormal way (an alteration in frequency or intensity). Therefore, when they see an abnormal behavior that mimics one they're familiar with, they ignore its abnormal aspects, and immediately pronounce it to be "normal" due to its familiarity. Not that I'm suggesting that fetishes are necessarily abnormal; they can be quite harmless and sexually pleasurable.
Of course, like with any human behavior, there are large degrees of variance. Some people have a mild fetish, while others have a very strong one. For some, the fetish comes and goes over time, or appears after a certain age or a specific experience. So long as they do not involve anything dangerous, illegal, or maladaptive (harmful to oneself or others), psychologists view them as normal variations of human sexuality.