As you said, some people do, some don't...

If you're looking for a full bodied debate or discussion about preference, you might wanna go to the Roleplay Discussion and pose the question there for GMs and people looking to join them. 

But otherwise you sort of answered your question, as some do and some don't.

Your thought that GMs get "a lot more people" is different from what I've experienced so I don't ever make a RP without first gauging interest and adjusting concepts based on feedback from potential players. But erm...like I said, it just depends. And I'm still unsure as to why you need "help" with said question, this is more for issues with the site or hiding unwanted posts, that sort of help on the Guild.