A Server that Auto Permbans people for breaking 1 block

Here is the story:

I was scrolling through a Minecraft server list to test out random servers to see what they had to offer when I randomly came across a server on the list, copied the IP and joined. Upon joining everyone was giving me some very friendly welcomes. I walked across the spawn and it was average looking and the server had around 10 players. One of the previous servers had joined had a very annoying antibuild, you'd simply click your mouse and around 8 "You do not have permission" messages would spam you, very annoying. I decided to try it ont his server so I broke one glass block at spawn and within seconds I saw "You have been jailed" and someone said "Oh Dear" in the chat. I asked why it was happening and they asked "What did you do?" and someone else said "You broke something?" which I admitted to. I then ask them this simple question "Have you ever heard of WorldGuard?" and they just said "Read the rules" which I could not find anywhere. Within a few seconds it told me I was permbanned. I'm totally going to get suspended and permbanned. Possibly even arrested who knows.