Why doesn't oil burn and produce smoke at restaurants?
Restaurants have massive fans.  

Commercial deep fryers have temperature control.
Example temperature control unit:



And massive heating elements (notice 4 temperature controls): 

  

Massive heating elements allows for even delivery of heat. When you drop frozen fish it has to kick out some heat but it is careful not to get too hot via temperature control. The temperature gradient alone causes good mixing.  When you heat fresh oil you can see it stirring around.    

If your oil is burning and producing smoke then your deep-fryer is too hot.  Even most home fryers have temperature control. Or you are possibly using the wrong oil.  A cheaper home unit will have a smaller heating unit so it will have more trouble with maintaining a constant temperature but a temperature controller near the heating element should prevent any oil from burning.