E.g. clerk, store-man, would be glad to hear of more roles during those times.
One bit I recall from "How to Feed an Army: Recipes and Lore from the Front Lines" - (Jim Lewin and P.J. Huff) talked about how difficult it was to get bakers. Aside from not being glamorous, and perhaps reflecting poorly on a man's bravery, the ovens were apparently unpleasant to use. Temperature was approximated by how many seconds you could stand to have your hand near it.
The army tried to attract bakers by allowing friends to sign up and serve together (as opposed to being trained and sent hither and yon by necessity). The armed forces certainly saw a need for non-combat roles. I don't know how successful this promotion was, however.
Allow me to tell you a tale about the New Zealand Fourteen.
New Zealand introduced conscription for overseas service in 1916. Prior to this, New Zealand had conscription for territorial defence only. Whilst conscription was widely supported in New Zealand, there were those that refused to comply with government legislation, some on moral and ethical grounds, some on political grounds and others on ideological grounds. The New Zealand government had no system in place to adequately deal with those that refused military service save to imprison them until they relented and complied with legislation or were deemed to be real conscientious objectors (hereby referred to as CO's) and released.
In 1917, the government reviewed a number of CO's and decided that fourteen of them were to be embarked and transported to the front in France. These men were labelled 'defiant objectors' and it was believed that they were not genuine objectors who objected on religious grounds. Three men were discharged due to illness en route (they were imprisoned aboard ship in miserable conditions) and another was recognised as a genuine objector and returned to New Zealand. The other 10 arrived in France where four were persuaded to comply and wear the uniform whilst the remaining six were subjected to field punishment. During the First World War, Field Punishment no. 1 was used to punish servicemen who committed offences. This punishment consisted of the offender being affixed to a stationary object for an extended period of time. This was highly uncomfortable and often painful as the object was not necessarily straight and so forced the offender into unusual positions. It could also be humiliating though some offenders wore the punishment as a badge of honour. Members of the New Zealand CO's were subject to this punishment and a number of them were convinced to serve as stretcher bearers to escape the punishment. One of these men, William Little, was actually killed in action serving in that role.
The remaining four CO's were subjected to continued field punishment. One relented and agreed to serve as a stretcher bearers whilst the remainder were ordered into the front lines. One refused and was brutally punished by being dragged across the rough ground and thrown into a shell hole. He was injured as a result and was discharged and returned to New Zealand. Of the remaining two agreed to be a stretcher bearer whilst the last, Archibald Baxter, maintained his defiance and was subjected to brutal treatment as a result. He was starved, placed in dangerous locations (likely in the hopes he would be killed) and beaten by officers responsible for discipline. He was hospitalised due to poor health as a result of his treatment and eventually declared mentally unstable, even insane. After this, he was returned to New Zealand.
As the New Zealand history site explains, the treatment of these men indicates that lack of a clear process for dealing with those men who refused military service. The best they could hope for was the persuade CO's to relent, abuse and punish them if they didn't in the hopes they would relent and eventually give up.
Sources:
King and Country Call - Paul Baker
The Oxford Companion to New Zealand Military History - Ian McGibbon
New Zealand's Great War - John Crawford and Ian McGibbon