You have to remember that they did not 'give' their lives it's rather they had their lives taken from them. When you remember the 1st world war when wave after wave of men were ordered to climb out of the trenches and run at the German machine guns or face being shot by their own officers it makes you realise just how bad things were.
They WALKED into the machine gun fire, shades of Duke of Wellington era thinking, hence the high casualties.
A disproportionally high number of junior officers were killed due to their very distinctive uniform. After about two years afair, they changed to aviod being a sniper magnet.
Part of the WW1 'rules' were that both sides held fire whilst medics collected the wounded and carried them back to the trenches.
Don't know where you got that one from. A lot of soldiers died in no-man's land from their wounds because the medics were not able to get to them. Even at night when a lot of medics went out, flares were sent up and snipers were active.
Apart from the 'Christmas day' truce there were informal agreements between opposing soldiers where warnings were given before bombardments or 'show displays' for visiting senior officers. These agreements were usually only active until one of the regiments got rotated.
See Professor Richard Holmes's book 'Tommy' for an exhausting account of the soldier in WW1.
I was in Crete a few years ago and went to the Suda Bay War Cemetry and I was shocked by the number of grave stones with no known identification.
Do we really remember them? Once a year if dead.
If alive and injured we forget them very quickly and they are regarded as a burden by society.