ampplaca it's probably just a bug on webnovel's behalf. I don't see the need to get all angry about it. how many typos/errors/grammar mistakes can you find throughout their site? probably 2 million. they probably just wrote that for when they first introduced coins and not fast passes, but forgot to change it when they implemented fast passes. I don't think it's that big of an issue as long as you can read the rewards for the daily missions, where it clearly says what you can earn coins for and what you cannot.
again, there are so many free novels on this site. I don't see why it's such a bad thing to step away from the contracted/translated novels for a few days to read some of the free novels that are probably pretty good as well, and get some farming in the meantime. it's not like when you're farming, you're suffering b/c you're reading a novel you don't want to read (and if you are, that's kind of your fault). plus, for even some translated/contracted novels, farming is an option as well (if you're under the belief that only contracted novels can have any quality)