Earlier quoted context omitted.
Disgusting? So if you see a sign on a car for sale that says $19,95 because a digit fell off, the dealer is obligated to sell it to you at that price? People and systems make mistakes, that doesn't mean it's "disgusting" that they protect themselves financially from those mistakes.
The price sticker is an advertisement, not a binding contract. See https://en.wikipedia.org/wiki/Invitation_to_treat
(On the other hand -relevant to the topic- an agreement may be declared void in the case of "obvious error"; so Fanduel could possibly have been off the hook if they had been operating in .nl .)