I am a person who quite often signs up and doesn't post. The reason i sometimes do it is i sign up to be able to read the forum if you make people have to sign up to read or if if there are sections hidden completely from guest view. Admin and email verfification sometimes put me off then i don't activate my account or when they do i don't want to post or i don't have time and sign up to post another day then forget or when i have time i don't want to.
Email activation is always needed without it you're leaving yourself open to spam attacks. You should also block all free/blackhole addresses (I think I have around 50+ blacklisted :lol🙂
It depends really , for a forum thats new , the member always helps , but as you grow some may want people who arent gonna spam and will vericate their selfs as that means there more inclined to post
Seriously though, as long as you have Visual Confirmation thing, then 99% of spam bots will be stopped. My forum has nearly 350 members and we haven't had any problems with spam bots. Email activation really isn't necessary and is very annoying.
Visual confirmations stops the bots but humans are just as bad and email verification goes some way to stopping them apart from when they find a temporary email that we haven't banned then sign up up loads of random ones from that domain and then can click the links ect. This goes a bit of the way to slowing them down and making the experience a tiny bit annoying for them as that will take longer to set up accounts. This is the reason we have it at the moment.
That's happened to me too. There are like three members that don't post. So the rest of us who do post have to pick up the slack for that member. What I'd have to do is PM these members and encourage them to post more. I even had one person join and do nothing more than PM advertise to me.