It can not drain the bottom of the bowl through the needle and seat if the seat is at the top. There has to be a rust hole or some funky siphoning going on. To truly find out if the float bowl is dry, pull the top.
I would bet the accelerator pump is not providing enough of a shot to get the engine started. In my opinion, it's standard practice to give the throttle a pump before starting a cold engine. Back when carbs had automatic chokes, you had to hit the throttle to activate the choke and at the same time shoot a little fuel into the carb.
