The problem with vanity addresses is also that people are lazy and would only compare the first few chars.
So it you had the address 1BATMAN2a2hqZdYv7WN7iy5hcGTUoedAnG than someone could create 1BATMAN2amC8jszfAZQ4EzefiDFSRkjpnG and people would think it's the same address.
How can we solve that kind of problem?
You can either
a. change all of mankind and make them compare more than just the first few characters
b. not use a vanity address
I went for the second option.
I don't get how people manage to send bitcoins to the wrong address though..why not just copy-paste the address? If the receiver didn't paste the correct address, it's their fault. So even if two vanity addresses look similar, it should be easy to distinguish between them
Copy paste does not fix this problem.
Say you are a well known organization (called Batman) with a vanity address listed for donations. (e.g. 1BATMAN2a2hqZdYv7WN7iy5hcGTUoedAnG).
I could easily create fake homepages that look as if they are affilitated with Batman. On those I would put a "fake" vanity address (e.g. 1BATMAN2amC8jszfAZQ4EzefiDFSRkjpnG).
People would see that it says BATMAN and thus not question the originating homepage any further.
Copy, paste, send bitcoins, --> I have now bitcoins that should have gone to the Batman organization.
(you can substitute Batman with any well known organization that excepts bitcoins)