The thread title should be "Kyle trial." It rhymes! We should always refer to the mob's intended victim as Kyle, not Rittenhouse. This humanizes him, in the same way that referring to Martin as Trayvon humanized him, and made him more sympathetic. Americans must start to use language as a weapon, in much the same way the enemy does. (Without the chronic mendacity, of course.)
Iirc he had just been released from a mental hospital or jail earlier that day. The bag held some of his personal stuff like toothpaste, hair brush, etc. Depending on what was in there it could have been enough weight to effectively throw.
And if you're being mobbed by a bunch of fascists/racists, as Kyle was, you might feel it necessary to assume the worst about what might be in the bag. That's the kind of thing Leftists can't grasp, unless it happened to one of their own.