How is it legal to make up a fee then offer a paid membership to avoid the fee you just made up? How is that different from the mob guys that would collect your "insurance" membership so that you didn't incur a "business burned down" fee?
All of that kind of stuff is illegal and/or regulated in Europe. It's not perfect mind you, but it's trying to be better. Another good example are car rentals, they can offer you non-required add-ons but other than that, the price you see on the first screen is gonna be your final price.