I'd go a little farther and say that if there are impractical scenarios to avoid the fee it still must be included. (Say, no fee if you pay the fare in Timbuktu.) Advertise it based on the 95th percentile of what actually happens.

That's very easily solved: The minimum total price of all possible selectable options is the cheapest price that can be legally advertised. Treat non-viable options that just exist as a false baseline as false advertisement, just like it's already illegal to e.g. send out a flyer advertising TVs for $1, but there's only one available at the other end of the state/country.

It's really not a practical problem in any country that has the appropriate laws. The only thing it takes to fix this is the political will to do so.

I recently ordered cake for $x, with a mandatory selection of "size". The only possible size was "large", which cost an add-on fee of $3. Just make that type of stuff illegal yesterday. Absolutely nothing of value will be lost.

The ACTUAL solution to these problems that HN always seems to be allergic to (because technicians prefer technical solutions, but humans aren't technical) is to make your court system extremely hostile to "clever" bullshit like this.

This insistence at having EXACT WORDS for things that aren't exact is just naivety, thinking the world is can be divided perfectly into categories if we just make the categories specific enough!

You cannot.

Excellent point. In the end the rules are simply words on paper, they must be enforced. So the exact verbiage is less important. But the lack of ambiguity is extremely important. I'll give an example:

- In the EU, what can legally be defined as a "sale" price (e.g. 20% off till Friday! deals) uses very precise verbiage that states an item must be at a certain percentage higher for a specific period of time (typically 30 days) to constitute a sale.

- In the USA, the regulations basically say that companies should make a good faith effort to not deceive consumers with sale prices. It leaves defining what a good faith effort is as an exercise to the reader (states).

The end result is that you have a lot more misleading price info in the States, since all manner of questionably legal manipulation tactics are used and enforcement of this is lax.