I think the all in betting on futures and losing if they don't start is a Australian.inititive, I think once the TAB use to give money back in bonuses sometimes, you should be refunded if horse don't start, but you take a punt and take ya chances but in reality it seems a bit weird that O Connor and the like are obsessed every week giving us odds, maybe it would be more ethical if they starting giving odds once field is drawn up, and strangely if you bet on the final field and are scratched you are refunded.
Also for sport there is no cash out on futures winners of leagues, that too is a negative, personally hard to know if anyone would bother without the escape clause, I could be wrong if so someone can correct me.
Betfair have cash out on futures, so should Entain, on a slightly different note Betfair has a pool of 363 million on the winner of the election, having a cashout allows people to bet with confidence, you can quit ahead or bail out early, if yoh choose.