Freeze may be uncommon, but it's far more common than the only ways to defrost in gen 1, since freeze lasts until KO or one of the only 2 ways to be defrosted happens. And both of the ways to be defrosted requires the foe to defrost you, which just isn't gonna happen since fire moves are not really good in Gen 1, and thus are not common at all in OU if ever. And Haze is a rare move found mostly on bad mons who can't really be viable in OU.