Disagree I don't think there would much difference in attendance between NL and CL. Its been proven loads of times that clubs that have gone up and down the leagues have seen little change in their attendance. Its understandable clubs want to compete at the highest most prestigious level especially if they have had a lot of success in the lower league.
I also doubt that Poole would disappear if they moved to the NL, it would seriously annoy some of their fans and maybe put a few off from attending but I bet more than 90% of the fans would still attend.