If it's one thing that is very evident about Dutch culture is that they are careful to close down all the loopholes. If you get on the tram and there's a ticket inspection and you say you forgot to swipe your card -- could be an acceptable excuse in Norway -- you'll still get a fine. There's no leniency, no second chances.
Gyms are horribly expensive and their pricing policies are very sleazy, because they usually don't have any short term membership options, you have to join for at least 3 months, or 6, or 12. As a PR bandaid they like to offer an "introductory lesson" or something along those lines. Basically, you can come in and use the gym once, for free, to sort of make up your mind before the point of no return. Sometimes they have an instructor accompany you to explain what is what. It's the same scam as "the cell phone for free", where they try to distract you from the 12 month contract.
At the gym I went to today they do have an introductory lesson. But this being Holland, there is an interesting twist to it. If you want to just come in once you can pay a one time fee of 15 bucks. The introductory lesson, which in theory is free, costs you 12.50. Then, if you decide to get a membership they will deduct that 12.50 from the price you pay later. So the introductory lesson is only free if it's not free, you see that logic?
This is a pretty eccentric attitude. In theory, if you wanted to bad enough you could come in once a month, try not to run into the same staff, and always go for the introductory lesson. If you could do it so that they didn't remember you, you'd get it for free. How many people would actually try that, though? One? Three? The money a gym would lose on this scheme is pretty negligable. More importantly, anyone inclined to go to such lengths probably isn't willing to pay for the gym anyway, so that money wasn't yours to begin with.
But this is a loophole-closing culture, they don't want to run that risk. In Norway the social stigma of being found out and feeling embarrassed is deemed sufficient in such cases that basically noone does it. But the Dutch are not satisfied with that, they need policies that remove any room for such creativity.