Or just hitting him over the head with a rock while he slept.
Forager societies more closely resemble middle school than modern life. In modern life, you can get in a fight at the bar and not see the person you lost to for weeks - if ever. In middle school, you lose a fight and you have to see that person every day for the rest of your life - unless you skip town (leave the tribe) - which appears to have been somewhat common.
Thus any fisticuffs victory will be hollow, as the loser can simply murder you one day when you least expect it.