It is paint, period. You are not dipping anything. You are painting with a spray can.
Dipping tools into the plastic coating is how Plasti Dip got it's start; you'd open a can of liquid plastic, dip your tool into it, pull it out and let it dry.
So the company name was a reflection of their original product; later they changed the product so you could also spray it, but they kept the same company name. Just an expansion of the product line.