Porn is all bareback, and it's for the viewer not the guy involved's pleasure. Neither are great qualifications for an escort.

 
That said, I don't think that Porn stars "give terrible [escort] service" as a rule. There are reviews of pornstars on this site that seem to be fairly good.  

 

 
Personally, I don't have much interest. There are some safety concerns and I don't think that your Bang (literally) to Buck ratio is very good.