Why are there so many terms for masturbation?

masturbate
bash the bishop
beat off (UK)
beat the meat
choke the chicken (US)
fap
flog the log
jack off (US)
jerk off (US)
play pocket pool (UK)
play with oneself
pleasure oneself
service yourself
skeet (Canada)
spank the monkey
toss (primarily British)
toss off (UK)
wank (primarily British)
wank off (Britain)
whack off
mastuprate
frig
diddle (female)
jill (female, vulgar, slang)

via Wikisaurus:masturbate - Wiktionary

 

 

 
 
Applying lip gloss
Bathing the kitty
Beating the Beaver
Checking for depth

Checking for the jackpot
Checking the pulse
Cleaning your fingers
Clit-o-Rama

Digging for my keys
Diving for pearls
Doing the two-finger salute
Excavating the Tunnel of Love

Exploring the bush
Fishing for cumpliments
Fucking without complications
Gagging the lips of love

via womanaboutsex.com

and so on and so forth...?  you can probably think of a dozen of more to add to the list off the top of your head.