Didn't think that scene added anything to the movie.
It was a good device to put Horn and Coble together and set the plot and theme for the rest of the movie. It also introduced Horn's horse which was a significant fixture in his life at that time.
At the same time, this scene was able to portray Horn as a fearless individual, which was also central to the movie.

Didn't think that scene added anything to the movie. McQueen played the part like he was the village idiot. Then Corbet mops the floor with the character.

Some bikers can ride their bikes with no handlebars but Tom Horn can ride his handlebars with no bike.

Too bad Tom's not around so you could call him an idiot to his face.

Corbett is the idiotnot knowing who Tom Horn was

Tom horn had fought and bested and faced much tougher men than that boxer.

Men back then weren't cowards like most these days. American frontier men like Tom only said what they believed and would fight to their last breath to protect what was there's, in most cases that was only what they were carrying but most of all it was their freedom, their ability to travel without any man telling them other and anyone they felt had wronged them or taken what wasn't there's to take would face a biblical response.
To compare Tom with a typical man of today (American or other) is like comparing apples & oranges they are no longer the same.

Besides, he was acting "kind of like an a**hole".

I'm guessing Tom didn't know who Corbet was and didn't care. He wasn't champ yet
Mongo like candy!

Harley's are for cross dressing sissymen. I mean it.

Hey, I'll try that, NOT!

I'd agree. It is much better to walk into said bar and offer a joke or two:
Hey, what's the difference between a Harley and a vacuum?
The dirt bag is on the inside of the vacuum!
-OR-
Hey, what's the difference between a Harley and a vacuum?
There is no difference. They both suck.
Raylan Givens: You make me
pull
, and I'll put you down.