Because they wont get caught on the saddle and they are just nicer to wear.
It's so they won't get caught in your stirrup and they slide out easier and if you wear like joggers, since there is no tongue in horse riding boots it won't get caught in the stirrup.
longer riding boots are better in my opinion as they make riding more comfortable for both horse and rider. Your appearance also looks much better with longer boots.
The tall riding boots of today are the ancestors of boots worn by 17th century British soldiers. On the battlefield these tall boots protected the lower legs and gave the soldiers better contact with the horse's side.
as long as they are strong boots
shoes with a small heel riding boots or jodphur boots are best
you need a helmet, riding boots, riding pants, and a crop( if your horse is slow ). you can find these things at the store Horsing Around.
Boots or sneakers.
kijiji is a good start.
Riding pants are flared to provide more comfort and flexibility while riding a horse. The flared design allows for easier movement of the legs and provides a better fit over riding boots.
I would reccomend Dover Saddlery
Unless you're riding for show, or in full dress, it doesn't matter as much what kind of boots you wear. As long as the boots have a good heel on them so that your foot doesn't slip through, either paddock boots or tall boots can be worn. (Or any other pair of boots.)
$40 to $400 in Australia
One can purchase men's riding boots from many different places online and offline. One can get them from Amazon, Ebay, and any other horse riding business.