War is sweet to those who have never experienced it
(Pindar, fifth century BC)
Pacifism was pretty strong in arts and literature. Which should not be surprising given that this is the period just after WWI. Proponents were e.g. Carl von Ossietzky, Kurt Tucholsky, or Erich Maria Remarque. In the arts, there were e.g. Otto Dix, Hans Grundig, or Ernst Barlach. A counterexample might be Ernst Jünger, though I am not really familiar with his work. Note that all of these (except Jünger of course) had been silenced by 1936,
During the Weimar republic, large parts of the elites (public servants, teachers, judges etc.) were rather reactionary. Few of them had actually seen the war and so they did not have much sympathy for pacifism. That the inter-war reduction of Germany's military potential had been imposed from the outside probably did not help.
Among the masses it is of course hard to say how far support for pacifism went. The remilitarization of the Rhineland was a matter of national souvereignty and it was quite easy to argue that it was unjust that Germany could not deploy troops there. That there was popular support for this move does not mean there was popular support for waging war against other countries. Indeed, Joachim Fest (in "Hitler") argues quite strongly that the war was unpopular in 1938 (during the Sudeten crisis) and 1939.
rs.29 has pointed to organizations such as Stahlhelm, Reichsbanner, Rotfront and SA. These were what one might call the paramilitary wings of the different political parties. The Reichsbanner was associated with SPD, DDP and other democratic parties, Stahlhelm with DNVP (reactionary/militaristic), Rotfront with the Communist party and SA with the Nazis. These organizations were quite large and to a significant degree staffed by WWI veterans. Reichsbanner was the biggest of these organizations with 1.5 to three million members. The Stahlhelm had about half a million members.
I do not believe that the existence of these organizations invalidates the points I have made above.
These organizations were meant to be used for internal politics. They were never supposed fight Germany's next international war.
Pacifism does not mean I cannot hit you back if you hit me. The Weimar republic had lots of armed power struggles in its first years, and lots of WWI veterans. So it seems somewhat natural that parties would have paramilitary wings.
As I understand it, the question is about pacifism as the rejection of the use of military force as a means of international politics. rs.29s comments seem to be about attitudes re. the use of (para)military force as a means of internal politics.
This is not necessarily the same, see e.g. American attitudes re. use of force abroad or at home. As a counterpoint one might take Afghanistan, which last had significant troops outside its current borders in the 1820s (I think) and had lots and lots of wars in within its own borders since then (Afghanistan does have some border conflicts with Pakistan, however)
Another good point by rs.29 is that field marshal Paul von Hindenburg, one of Germany's de-facto rulers during WWI, was twice elected president of Germany. The second time there were even quite accurate predictions about the political consequences of electing Hindenburg by the communists ("Who votes for Hindenburg, votes for Hitler. Who votes for Hitler, votes for war.". Note, however, that they did not accuse Hindenburg of wanting a war.)
Hindenburg won his first presidential election against a catholic and a communist candidate and his second election against the same communist candidate and Adolf Hitler. Given that elections are decided by mixture of reasons and people do not always get what they expected, I would argue that this is no conclusive proof of Germans wanting another war.
The French also had a president over much of the 1920s who had been an active part of the wartime government, so the correlation between wanting war (or not) and the WWI career of politicians one voted for may not have been particulary strong.