Travel visa laws are simple: they're not designed to be used for what amounts to virtual citizenship. Is the penalty unfair? I don't think so. Dennis is no stranger to travel and the rules/regs that go with it. Anything that happened here he brought on himself.
I think the point was:
laws don't always make sense. Sometimes people, who made the laws just made mistakes, because they were just people. Its the right and duty of people in a democratic society to spot such unfair laws and try to change the legislation.
A law is not correct, right or fair, just because it's happens to be a law.
Fines for making a mistake can be fair or overly harsh. And knowing the situation of Denis lots of people think, the fine is too harsh.