Currywurst in Germany is like fish’n’chip in England or hot dog in the States. In general, Germans seem to love sausages or “wurst”, there is bratwurst (grilled or pan-fried sausage), wiener wurst (hot dog), Blutwurst (sausage with blood) or weißwurst (boiled white-colored sausage typically eaten with sweet mustard) and Conchita Wurst. XD
Also, bratwurst doesnot equal bratwurst. There are regional differences, e.g. Nurnberger Rostbratwurst, Thuringer Rostbratwurst or Berliner Bratwurst. However, currywurst is the favorite way to eat bratwurst nation-wide: sliced in curry ketchup usually with bread or fries.
There are also variations in the spicyness of the sauce – from mild to freaking spicy (over 16,000,000 Scolville).
I like to eat Currywurst rather mild.