This is obvious to most queer people, but might be counter-intuitive at first. So let me explain.
Any large gathering of people is likely to lead to adults hooking up. This is a fact of life, especially when alcohol is involved.
Having a convenient way to know your status onsite is a great way to allow consenting adults to make informed decisions about their sexual health, especially if they’re not generally promiscuous and aren’t in the habit of getting tested regularly.
This is brilliant, and more places need to copy this. There are massive outbreaks of STDs, and the demographics are changing in a very concerning way for new segments of the population, but particularly women in the UK and women in the US.
Straight men are also very much at risk as schools de-emphasize sex ed, or never taught it well. Regardless of your orientation, you and your date(s) should be getting tested regularly, and wearing protection is always a good idea. If you are doing sexual tourism with multiple people, you can get on a medicine called PrEP that will dramatically reduce your chance of getting HIV as long as you consistently take it. Outside of terrible bloodborne Pathogens like hepatitis C and HIV, there are a number of STDs that can cause organ damage, even if you are man. Many are fully curable, but they must be caught before they start doing organ damage.