If we have known lots to be some sort of sacred activity that could act as a guide to help make some decisions after the outcome, can we not then classify or tag casting lots and drawing straws, as a kind of gambling activity?
I've always thought of gambling to be an activity that would involve you staking some amount of money. If there is no stake really, calling it gambling becomes difficult. Casting lots and drawings straws, or even games like rock, paper scissors and flipping coins are all for decision making or selection method.
When you see football officials flip coins for the teams to pick a goal post, you cannot call that gambling, so it is the same with the other selection methods, you cannot call them gambling.