It is so hard to even try to explain the way that justice works in Greece. Maybe it is easier for someone from Nigeria or Colombia to understand but almost impossible for someone from a first wold country. I'll try though.

As you, correctly, find out, this law is active from January. Since then there are thousands of motorhomes, spending the winter and spring, all over Greece. I see a few dozens of them every day at Nafplio. And yet the law has been used only once at one parking used by caravans in the town of Akrata. You tried to find a reasoning behind that law. I'll give you another one.

Imagine that a hotel or camping owner in Akrata is annoyed by the caravans parked on the municipality parking lot. But he can't do much about it with the existing law about wild camping. But he is a member of the government party since his youth. And his brother in law works in a ministry. So he calls his brother in law, reminds him how much work and sacrifices he has done for the party and asks as a favour a solution for his problem. The brother in law visits the minister and he agrees. The fact that there wasn't any new law about wild camping in the government's plans was no reason for them to stop. They added a paragraph in an irrelevant law and problem solved!

ANY similarity to actual persons, living or dead, is PURELY coincidental. :)

Now I can't tell you that they won't use this paragraph (because it is actually a paragraph in an irrelevant law) ever again. But I really doubt they will. And your car cannot be taken as caravan even with the most flexible interpretation of the law.

But then again I might just saying all that because I want you to come :)