In the 1970s and early 1980s parties like that were common. In San Francisco, Los Angeles or New York if you were half way attractive you could easily get yourself invited either to a loft, apartment or private home where the parties could be held. There were also sex clubs (both gay and bisexual/straight in these cities were buying a membership gave you entrance to bliss).
In Europe Amsterdam was one of the centers of parties like this. People would go Amsterdam to spend the weekend fucking. I also attended parties like this in Munich, Vienna and Athens.
Sadly, the AIDS epidemic brought much of this kind of entertainment to an end. I'm most pleased to see it being revived by the young and only hope they are careful and practice safe sex. If the health rules regarding this beautiful, enjoyable and horizon expanding behavior are carefully observed, all of our lives with benefit, and all of our bodies will know more pleasure than our mortal minds could conceive of.
I'm one of the lucky ones, I was there, I survived, and my excitement over the return sexual celebration by todays youth thrills me to the core.
If it feels good, do it!