If you can go to jail (and be deported in 24 hours) if caught working (or making income) in Belize while here on a tourist visa (or extended tourist visas) it is bit more than operating int "spirit of the law". It is a just illegal as using drugs in your own home or driving while intoxicated.
Rosa Parks could go to jail for sitting in the front of the bus. Doesn't mean that she didn't do the right thing and it doesn't equate her actions to those of driving while intoxicated. Civil disobedience is a bedrock of a free society. It's about doing what is right over what is legal. Yes, if you are caught (and prosecuted) you must pay the consequences... but there is an ethical consideration to every legal decision.
Just because there is a law saying you shouldn't do something, that doesn't mean you shouldn't do it. And just because there is a law saying that you should do something, that doesn't mean you should. Laws are made by fallible humans and while they are often made with the best intentions, they tend to have unintended consequences.
I'm all for working to change a bad law, but your black-and-white, law-is-god perspective is a very dangerous one. Everything must be viewed through pragmatic glasses for the most ethical outcome.
It is very healthy to question authority and is in fact the only way toward a better society.