The army employs musicians to provide music for ceremonial occasions including showing respect for fallen soldiers. That is the task for which they are trained. My Dil is a professional musician, with a music degree, who joined the army in order to perform this role. By performing this role, she releases a "professional soldier" for other duties.
It might seem like a stupid job and ridiculously archaic, however, in the event of a terrorist attack or act of war, communication systems can fail. Mobile phone networks are jammed and power outages occur, so potentially, the traditional role of an army musician to play "calls" to communicate may still have a role to play.
Pipe or Bugle Master positions are used to train future band leaders and soloists and also to teach "calls" to soldiers. It's a two way teaching/mentoring system. It's a job my DiL would love to be promoted to.
An Army musician needs to practise handling ceremonial attire and slippery soled boots whilst marching into gusts of wind, sleet and hail, keeping in tune and remaining to tempo. The sound of a practising musician isn't always a listening treat! Playing reveille is difficult to practise "properly". It isn't the same thing at all to play at 11 0'clock, or indoors - learning to wrestle with a cold instrument at dawn in all weathers requires practise. Even on a military base there are sleeping babies and other personnel whose work/rest shouldn't be disturbed so there only a few military bases where soloists can get in the essential practise they need.
When my Dil isn't practising her music drills she works as an administrator within the army base. She's also received basic military training, so in the event of a terror attack on a public gathering at which she is playing, she will be able to take on a first responder role.
Based on a salary of £37k with 6 weeks leave and a 40 hour week, the cost of a 15 minute reveille call is £5 or £35 per week This seems IMHO excellent value for a back up alarm system on key sites. To train a musician as a soldier and first responder and employ them as part-time administrators to save them twiddling their thumbs waiting for an emergency or a state funeral also seems a good use of public money.