But coach Lane Kiffin is throwing him a bone this week and putting Banner on the travel squad for the team's game against Washington. Banner grew up in Tacoma, Wash., 30 miles from Seattle, where the game will be played, and was raised a Huskies fan.
Banner was elated to find out he'd be accompanying the team, even though he won't be playing unless something drastic happens.
"If I was gonna pick any trip, it'd be this one," he said this week.
The mammoth 6-foot-9, 335-pounder expects about 30 family members to attend and anticipated he'll be giving out a "a lot of love pats and I-miss-you's" on the field afterward.
Teams are allowed to take 70 players on conference road trips. Kiffin said NCAA-mandated scholarship limitations and normal injuries have left the Trojans with less than 70 available players who they could count on in a game.
"We're not at that point," Kiffin said. "So we take some guys that never play and so that's the good thing about the sanctions. ... Zach gets to go on a trip home and go up there.
"Hopefully we won't be doing that for many years."
Banner, the son of former NFL lineman Lincoln Kennedy, said he was stressing to himself that it was a business trip, regardless of the game's location. The fact that he went to several Huskies home games as recently as last season doesn't matter anymore, he said.
"One thing that's cool about it is Coach Kiff is giving me the opportunity not only to go home and see the family, something I'm not able to do because I'm not from around here, but he's also giving me the experience of what it's like to travel," Banner said this week. "Next year, for my real freshman year, I'm gonna know what it's like to travel and not have it phase me."
His decision to attend USC over Washington and Oklahoma was a big deal in the Northwest in January. He said his "real friends" supported the decision whole-heartedly.
"They knew I wanted to be different," Banner said. "Usually everyone from back home stays home, but I wanted to be different. I wanted to see how my road could change on a different path."
Banner is one of two Trojans from Washington. Walk-on kicker Alex Wood went to high school on Mercer Island. Fifty Huskies went to high school in California.
The day after his high school graduation in June, Banner moved to Los Angeles. He hasn't been back since, and he may or may not have the opportunity to return home during the Trojans' brief holiday break in December because of basketball.
So this could be his only contact with home for a while. And he's learned to appreciate Los Angeles and USC, but he's not afraid to say he misses the Seattle area.
"It's not gonna be able to replace home, ever," Banner said of L.A. "But it is gonna be able to substitute for it."