Ignorance of the law does not excuse one from breaking. There is no freebie.
The world is a bitch in that it is your oyster, right up until you start impacting something everyone else is counting on. In that case, it is not infrequent for one to be made an example of.
That law student Latin there is a reminder that in spite of you "not knowing" something, the world still turns, you are expected to do some level of research, and there are people whose job is to just search for violations, and dispense a Notice of Apparent Liability to the perpetrator.
Hell, Amateur radio operators run what they call foxhunts when they notice something odd going on, because spectrum misuse impacts everyone.