Is it bad to run lawn mowers in the choke position?

Not really, but you are wasting your time and the lawnmowers life. You have some kind of obstruction in the actual fuel intake stream. Could be a simple adjustment of a cerburator screw which all lawmowers have. Ask a neighbor or some one that knows almost nothing about engines but he will more than likely know how to make the adjustment. The real answer is yes,you are starving your engine for air or fuel some way so you should have it fixed and believe me its simple.Don't let sombody sell you an exspensive new lawnmore for a simple NO COST ADJUSTMENT. Good Luck...