Not all of us. For me it's far more about the psychological aspect than anything-my base fetish is humiliation, albeit (usually) in a much more playful sense than traditional.
For me, tickling is more about the relief from tension, at least as the 'lee. The ability to shed the whole 'adult' mask and be driven to begs, blushes, and helpless laughter against my will--having the adult mask ripped off me by force by people who know how good it is for me x//D
As the 'ler it's about control, of course xD That part's no different than most people 😛
~K