For us it was because of infertility. We wanted a family and medical procedures are VERY expensive and not covered by insurance.
We decided that small gangbangs were the way to go, so we would not know who actually worked, it was prior to DNA testing.
We did it four times.
One time was hubby and four younger guys. They did me 12 times in one night.
The smallest was him and two guys.
In the end it never worked, but was a lot of fun.
We ended up adopting.