Leaderboard Boost Item
Ok you asked how does a person get 10,000 points very quickly...
They are willing to spend a lot of gems very quickly.
I call them the Yellow Boosters Club.
They buy a yellow booster for 30 gems, usually every time they sign on to collect points.
Yellow Boost gets you 72 points for collecting pigs instead of 36.
Planes gets you 12 points instead of 6.
But this is how they get the ten thousand points...
Every LB, there's a 15 point Boost Item for sale.
You can buy as many of them as you want.
This time it is an Ice Skate Statue.

Go to the person's farm that just accumulated all these points very quickly and you will find this item.
I decided to give this a try once to get the pet at the end of the milestones as I had run out of time.
First, I clicked the 15pointer Boost item, then the speed up button popped up. I clicked away 4 gems, then I swiped bucket over the 15 pointer and I got 15 LB points!
I also used the yellow booster for 30 gems because I would use less gems for the amount of points I needed.
(breakdown provided below).
To get 1500 points:
1500 LB points (no boost)
100 speed up x 4 is ... 400 gems
1500 LB points (7 gem boost)
67 speed up x 4 is 268 gems plus 7 gem boost is ... 275 gems
1500 LB points (30 gem boost, double points)
50 speed up x 4 is 200 gems plus 30 gem boost is ... 230 gems
It took me less than 2 minutes to speed up 50x and get the milestone pet.
I did this in the last five minutes of the Leaderboard just to get the milestone pet.
Ok but now you have the group that wants the main prize that only two players win in any Leaderboard.
They are willing to buy and spend a massive amount of gems to obtain the prize and the gold trophy.
These players usually use it from the start, a declaration so to speak, some use it at the last minute, erasing the countless hours of hard work put in by fellow farmers.
That's basically how it is done.
Anyone that is willing to spend gems can get a massive amount of points very quickly.
Ankavale1000 posted the breakdown for points above once so I used her information above.