When Is A Walk Not A Free Base ?

[jjohnson]

NFHS RULE BOOK
2-63
Walk. A walk is four pitches thrown out of the strike zone awarding the batter first base. (Doesn't say without liability to be put out)

8-2-4 The batter-runner is out...
The batter-runner fails to advance to first base and enters the team area after a batted fair ball, a base on balls, a het batter (F.P.), a dropped third strike (F.P.), or catcher obstruction.

8-2-5 The batter-runner is out...
She runs outside the three-foot lane and, in thejudgment of the umpire, interferes with the fielder taking the throw at first base; however, the batter-runner may run outside the three-foot lane to avoid a fielder attempting to field a batted ball. (I don't see an exception here for a walk)

8-3-11
Awarded bases must be run legally.

I believe these four rule references is why the NFHS rules that "if on a walk, the batter-runner interferes with a throw to first while they are out of the running lane, THEY ARE OUT."