Are you serious .... monks have less hps then most other classes and the main feature of the monk is the ability to add more stat power to AC in return for loss of armor choices.
Do you seriously believe that most monks have **** ac? I have 2 points off of max ac possible on a monk and hit 74 self buffed with no tring ... I cannot even see why people like str monks .. i have seen crits on a str monk they are hitting on average what 13 points physical 26 more on a crit?
with an AC 74 self buffed i can solo amarath on hard (prolly could do elite but dont really want to try takes up to much consumables) With all the pots and group buffs i can hit 90 ac (not including store bought pots which i personally consider cheating so i don't)...
While i definately see how str monks are common amongst min maxers .. they are far from the best build for monks who enjoy the soloability .. cause having no AC and getting hit every time for 100 points vs getting hit every third time is a drastic difference.
I would seriously doubt that there are FEW dex based monks ...
aside from that ... quarterstaffs being finessable helps all finesse builds ... not just monks ... especially finesse AC builds that take a few levels of monk for the bonus feats and evasion.
Again Finesse Quarter staffs are not for DPS they are for stat damaging and crowd control at the most.