I think there is enormous pressure from males generally on what young women are expected to wear--whether in the West (particularly during teen years) or the GCC.  While women in the West have more choice, the pressure is still substantial.

The whole point of the cartoon is that we are all victims of our perceptions and tend to transpose those onto other people from other cultures.  For Qatarpride and SA and the others attacking the bikini-wearing woman (for all you know she is a Muslim from Qatar on vacation in Cancun) you are making the cartoonist's point.  Perception is everything.

Besides this in the funnies, we should be chuckling at our own prejudices, not defending them.