There is a great number of people that are suffering from HIV/AIDS that acquired the disease from other means than a promiscuous life style. There are Doctors, nurses, paramedics, firefighters, police officers, etc. that have acquired the virus "in the line of duty" so to speak and in some cases have passed it on to the person that they are in a monogamous relationship with.
Not to mention the large number of people who did absolutely nothing at all besides have a blood transfusion, or was given a shot with a contaminated needle.
I know there are tons of things individuals can do to try to prevent getting HIV/AIDS, but I strongly dislike the implication that anyone "deserves" to get it because of their behavior. That's just wrong.