Ack, you're spoiling their fun. It's not about joining the Scouts, it's about the AtTeNtIoN the mental parents get for causing drama. They don't want a gay group because then they'd all be the same and that won't garner attention.
It’s more along the lines that such an organization has little to no chance long term. A small percentage of the overall population are even scouts, a fraction of that would be homosexual. Basically a minority within a minority. Hard to sustain itself as a group. Probably Doomed to a downward spiral.