Sexual promiscuity imposes massive costs on the healthcare system. HIV treatment costs $1,800 to $4,500 per month, for life. The resources expended on treating those who contract HIV through high-risk sexual activity could have instead been used for medical research to cure other non-preventable diseases, if they hadn't engaged in that behavior.
But of course, it goes without saying that the vast majority of vaccine mandate supporters have never considered supporting laws restricting high risk sexual behavior. They would never have even entertained the thought, no matter what the facts. Their hypocrisy is staggering.