The core reason for nearly all human actions is the hope to achieve satisfaction on the short or the long run - that's also why societies have been set up in the first place. If a society is not able to ensure this goal, it only seems reasonable to make an effort to change it for good. Because it is your life and your fellow human beings' which are and will be majorly affected by this environment. So this is not a question of cultural perspectives, but rather of human sense.
Nevertheless, as cultures and societies are shaped and carried by individuals, there are always persons who selfishly evoke peer pressure and abuse ideological, social and gender specific differences for their own interests. But as long as you profit from it or are not directly victimized yourself, it's quite easy to close your eyes and refer to cultural tolerace. Still, (culturally tolerated/legitimized) discrimination and sexual expoltation has a long tradition around the whole globe. So it does not come very surprising, that women living in strongly patriarchic countries get silenced and loathed for making their abuse public and are officially declared disturbers of social peace.
Iman al-Obeidi's case is only one of plenty and I highly doubt that she would have contacted the international press for no reason, considering the consequences she might have to face. Even if she was a prostitute and therefore 'honorless' in the eyes of society according to emeraldrafael - why wouldn't this also speak for a misjudged martyr for human dignity, an attempt to make a change? Public opinions and social structures can be very wrongful, especially when they are based on prejudices and the lack of proper information. BTW: As far as I can read from different sources, al-Obeidi used to work as a lawyer (already posted links on page 1).
Furthermore, you can compare all professions to each other on a very simple level: They all involve selling your time, work and by this your body with which you operate (at least to a certain degree). What really makes the difference though are the cicumstances under which they are executed. For prostitution you don't need a graduation, however it is with no doubt a physically and mentally dangerous job. The majority of people who are working as prostitutes despite these risks, either don't have better prospects, are not aware of their situation or are being forced to - or more than one of these things. Human trafficking with the aim of sexual exploitation of women and minors e.g. is actually a very present, but highly underrated global problem with mainly (rich) western destination countries (inform yourselves!).
In any case, the larger framework of economical, educational, political and social affairs in which prositution and discrimination takes place is set and influenceable by societies themselves. So blaming socially disadvantaged members of the population for their chanceless situation while treating them as scum really speaks for a legitimate, honorable social order, doesn't it?