I'm not sure what that has to do with the discussion of spammers trying to access our site except to say that maybe I am banning legit users that may be using a VPN. Not sure. I will say this though, I use a number of criteria to decide whether or not to ban anybody. I will also say that probably 100% of those who sign up and state that they are from New York, Alabama, and almost everywhere else you can think of but their IP addresses clearly show that they are from China, India, etc., get banned. Is it possible that I occasionally ban a legit member, possible but not likely in my opinion. If people are so paranoid that they falsify their information when signing up, I really don't care that they get banned. I can assure you that very few legit people get banned when I use the multiple criteria that I use. Not only IP addresses but other things also that I won't reveal publicly.
I very occasionally get an email from somebody who says that their registration was denied due to being on a spam list. That has never been one that I banned personally but was caught by anti-span software that I have installed. I usually trade a couple of emails with them to verify that they are legit and then set up their account manually. I have never, a single time, received an email from somebody that I personally banned based upon the criteria that I use.
I think that I go above and beyond to keep our site free of spammers. I will continue to do so and if I inadvertently ban a potential member then so be it. If they contact me, I will correct it but otherwise, I don't give it another thought. Mine is not a perfect system but it is serving us well.