But they're not giving all horses an equal chance. One is 3/10 while another one is 300/1.
If the fav and 2nd fav finished priced order, I can't imagine the forecast paid more than evens. Assuming the 300/1 had no chance, then you're only left betting on the 20/1 shot finishing 3rd ahead of the 33/1 shot, which again would probably be Evens at most.
I don't know what way is was actually worded, but to me the 9/4 applying to the naming of the 1st, 2nd through 5th in the correct order is much more realistic than just naming the first & last home, the latter of which I would be all over!
This reminds me of a few weeks ago when some lad about my own age (20-23) was having an argument with the girl behind the counter. The offer on the PP screens was a straight forecast at 9/2, the fav to beat the 2nd fav. It was worded as "'Horse X' to beat 'Horse Y' 9/2". Horse X came second and Horse Y came 5th or something. The lad thought it was a match bet with the fav being 9/2 to finish in front of a horse lower than it in the betting. And he kept arguing it. Eventually an older man came up, explained it, and kindly said to go home, you've no business being in here. Snobby but quite funny at the time