Thread:Jr Mime/@comment-17737991-20140908035918/@comment-4568327-20140908202402

Proxies are often commonly blocked on Wikipedia as well, as are Tor anonymity networks, because just about anyone can use them and edit under that IP address, and sneaky vandals can under that IP address, make a mess, get the address blocked, and then disconnect, giving the next user a surprise. Dynamic and shared IP ranges, such as AOL, also suffer this unfortunate consequence. Sometimes, logged in users are allowed to edit from these IP addresses, but because that is often an abused privilege by vandals as well, it may be disabled and accounts wind up getting autoblocked.

It is more than just an inconvenience, but of a consequence of IP addresses and blocks/bans on them, not to mention it just seems a bit inconsiderate, messing up someone else's ability to edit.