Party Invite!?

So, out of the blue, I get an invitation to one of those "special parties." It sounds very hot, so I send in my info.

I get an enthusiastic response, saying there will be around 50 men there for a house party on Miami Beach. The host suggests that all will be seronegative, and all attending should be.

I wrote him back to ask if he really thought he could find a group of genuinely seronegative men in South Beach. He replied that condoms were provided, and encouraged.

If you're going to answer like that, what's the point of asking HIV positive men not to attend?