I would suggest that what the original customer did was theft. They would still be reaping the profits of their thievery had not stopped it.

Legality is the hard part, which is likely why this company went the way it did. Most people would prefer a 'This site is down due to non-payment' or a 'we are down'.

That's trying to swim upstream without a paddle, this is slippery enough without trying to on the right side.

I have no pity for fitnesssf, but that doesn't mean that the creator's actions are okay. (I'm not sure they aren't okay, either.)

Do remember, they are in a foreign country. Have you tried to sue someone outside of your country? It's not cheap nor easy.

And yet so very, very awesome.

absolutely. i used to dream about doing something like this to asshat clients i had when i was starting out.

it's kind of like the designer equivalent of quitting your desk job by kicking your monitor onto the floor and walking out giving everyone the finger. XD

From the developer or the client? I have little sympathy for clients who are given countless opportunities to pay their bills and yet keep ignoring them.