Why do cars steer the way they do? I'm not sure if this is the correct site to ask, because I could not find other site that suit better. 
Consider this picture

The top-state is the car when wheels are straight. I found on the  Why is chosen for steering option b, instead of a?
 A: the straight-axle steering is called "wagon steer" and it is not used in cars because if one of the wheels hits a rut in the road, the wheel gets caught, the whole axle pivots into a full-deflection turn, and you crash. 
A: If the entire wheel rotates like that, then where does the suspension go? Do you just pull the whole spring assembly out of the car when the wheels turn?
Also, consider how big the wheel well is in your car. Either this wheel well must extend into the car or you have to severely limit the turning radius. Do you know where the wheel well would need to go? Driver and front passenger's leg space, pedals, and the front door hinges.
There's also a lot more equipment to move, so the steering hydraulics need to be bigger, and the shafting needs to be bigger, and you can't have front wheel drive unless you have an elaborate differential or the transmission rotates, too, but then you need the engine to rotate. 
So, practicality. That's the reason cars don't steer that way. It's not practical. Definitely an engineering question. 
