What was their idea on how a war should be fought?

From the text:

Katczinsky won't budge from the opinion which as an old Front-hog, he rhymes: Give 'em all the same grub and all the same pay And the war would be over and done in a day.

Kropp on the other hand is a thinker. He proposes that a declaration of war should be a kind of popular festival with entrance-tickets and bands, like a bull fight.