President Barack Obama ran into an impromptu weed lobbyist in Hawaii

President Barack Obama ran into an impromptu weed lobbyist in Hawaii Tuesday -- when a hiker came face to face with the Commander In Chief and asked him to "legalize it on your way out!"? TMZ has learned. Obama laughed and continued on his way. 

It's no secret Obama smoked a ton a weed back in the day -- but says he's not a fan of the ganja anymore and has told his daughters it's a bad idea.