I agree with SJOGuy. Beyond that:

Why would anyone feel obligated to do that? If the chap is on two weeks' leave, he doesn't need all the military stuff - it's not likely he will be wearing more than his BDUs home and perhaps a Class A uniform to an event - if that. Other than that, leave is time to revel in wearing "civvies" (which you likely left home anyway) and get away from the military life and hazardous duty for a moment. And maybe no-one in line before him was an AC member.

If the military member is on orders, the airline allows him the 100 lb duffel et al; if s/he's not, they don't. If s/he's on orders and involved with OIF or OEF, with their accompanying family members, and s/he has access to the AC if there is no USO (I've never seen an eligible military member turned away from the AC); if s/he's not, /she doesn't, though I think s/he can still use the USO (LAX has one near The Encounter restaurant.)

As a veteran who returned to a sometimes less than enthusiastic reception from Vietnam, I do often guest a military member to the Club, or comp them a drink or two on board. But I'd not have any expectation others might choose to do this. AA was nearly always good to me when in, or out of uniform, with a very few exceptions - again regardless of uniform or not. That's a lot like life... and IMO the family and media, not the military member, made a mountain out of a molehill.

“He was wearing his army fatigues,” Melodie Sharpen said. “He had his backpack, which is Army regulated and he had his luggage.”

Gary Sharpen showed up with one 64-pound duffel bag, which is normally 14 pounds overweight. He wasn’t worried because he knew that American Airlines waived fees for active-duty military personnel. (He was so wrong! AA only does that for those ON ORDERS.)

The airline's policy says “military personnel on orders are allowed one bag in the free allowance up to 100 pounds.”

Sharpen's mother, Laura Lee, said not only was her son charged $50 in overweight fees, but the ticket agent was rude to him.

OK, maybe the agent told him s/he didn't care if he was headed back to the 'rock or not, because the policy is not concerned with where you are on leave from. Was s/he rude? Maybe, maybe not - but I am far from convinced, given the entitlement these folks who obviously love their soldier seem to be framing their statements in.