How many sites per subscription?

In most networks, I see 15-20 sites offered to users with each str8 subscription. I have noticed that the same networks, and others, don't offer as many gay sites but still charge the same kind of money per subscription. Why aren't gay sites offering the same value for money?

1. there are less gay sites

2. gay sites often offer more content

3. those bulk networks don't retain well for niches or smaller markets