Huh, interesting topic.
I wonder why people expect other people's mods to be free even though people put countless hours into them.
I can make my mod for pay if i want, that's none of your god damn business cause I made it. There's NOTHING to say I have to give my stuff to you just because YOU think that it should be free.
I, personally, wouldn't do this unless I was looking at making the mod for income as some sort of part-time job if it was that popular. Otherwise, I make my stuff available. I don't want to make my stuff for pay, but I will always have that right when it so comes to a point.