Not sure if they're aware if they have access. When flying UA and I see a military person of age flying, I give them an inflight drink chit (1Ks get 10 a year compared to AA's unlimited coach drinks and BoB for ExecPlats). However having learned they can't drink alcohol while in uniform the FAs would let them take a food item from the BoB instead. But I'll keep this in mind next time I spot someone in uniform prowling the terminal!