Locations 
Thailand.
While Phuket is a more popular and well known general tourist location in Thailand that includes sex tourism.  Pattaya is clearly a location that is dedicated almost exclusively to sex tourism.  I dont know Phuket that well but well enough it is bigger but probably has alot more non-sex tourists so if I were going to identify a place in Thailand if not the world I would mention Pattaya instead and I am tempted to edit.  I hazard a good guess that on any day there is much more "sex for money" going on in Pattaya than Phuket. But for someone considering the phrase "sex tourism" as not necessarily pejorative I have to qualify this conclusion.  
Note that "bar girls" in Thailand never refer to themselves as prostitutes and this probably goes for most of the general Thai population also.  Although I beleive that there are words in Thai for prostitute they mostly (at least the girls) prefer to call themselves "rented wifes" albeit for "short time" rather then "long time".  I therefore need to be qualify my Pattaya versus Phuket statistic in order to be accurate as excluding sex between husbands and  rented wifes particularly of the "long-term" married western kind that typically eventually end up with a large exchange of capital in the "wifes" direction whether during the marriage or at its end or both.  There is no such thing as a free lunch and "everybody pays for it". 
[Note that I neither intend nor consider any of the former comments to be either sexist (note women still get paid less than men and suffer loss of income during pregnancy and child rearing) and moreover consider them culturally aware (particurlay Thailand wise).  The fact is that almost all relationships of a sexual kind are commercial ones! One must be aware that labels, concepts, ideas such as "sex tourism" carry suggestions associated with Religion particularly Judeo-Christiam-Islamic (JDI) pejoratives thst underpin much of western if not most of the (Religious) worlds worldviews outside of some tribal, village, usually Buddhist and what I like to call "Giesha cultures": e.g. Japan, Thailand etc, versus "Virgin cultures" typically (JDI) that often revolve around even int he west to some extend the worhship and praise of female virginity before marriage. (Note that Thai Society is strangely contradictory in this regard  aren't we all!  but then Thai culture too has a long and more recent tradition of polygamy than the west.)  Perhaps some historio-religious criticism of these sorts o pejorative and cultural factors should be entertained in the article proper also.  I hate value laden western (and Religious) labels that dress themselves up psuedo-scientificly as culturally universal. Exploitation of the child aside their is vastly more "exploitation" going on outside of the sex busniess in the third world under global capitalism like Chinese factories where labourers - girls included - work excruciating long hours for a few Yuan or RMB.]