Wouldn't it be near impossible to visit one of these sites by accident just surfing within conventional domains like .com, .net, .org etc.?
You’d be surprised. Remember about 10 years ago someone squatted on WhiteHouse.com and turned it into a porn site. People thinking they were going to the White House website were greeted with carnality at its finest.
People using Tor are not your average Internet user, but I’m afraid this is setting a dangerous precedent.