Many words have different meanings, here is Webster's definition of the word fetish.
There are several people that pointed out they were too young so they could not have started because of a sexual feeling.
If you look at the fist definition I think we can all agree that we all probably fit into that with some degree....so by definition we all started because of a fetish (a strong and unusual need or desire).
Webster's Definition of fetish
: a strong and unusual need or desire for something
: a need or desire for an object, body part, or activity for sexual excitement
: an object that is believed to have magical powers
