Those outfitted for a fight were there to engage the expected Antifa rioters--and the Antifa folks were apparently too cowardly (or too smart) to show up.
That may be true, actually. Not that Antifa cared about them, but that the MAGA bunch feared they would show up. In which case, all it took was an incendiary speech to get them to break into the Capitol Building. Because they absolutely did do it, with the plainly articulated intention of stopping the ballot count.
I am still suspicious of the zip-tie guys, though.