I have no useful first hand knowledge but I have seen 2 movies.
In “the Patriot” (Mel Gibson), there is an unwritten rule where the snipers don’t fire at the officers. Gibson breaks that rule, killing a great many British officers angering Cornwalis but also demoralizing his army.
In “Enemy at the Gates” is the real story of a Russian sniper in WWII who kills a great many german officers.
Apparently, snipers have been despised because the snipers fire once which reveals their location and then the sniper moves on to another location. So snipers pick high value targets like Generals which makes them valuable but despised members of the miltary.
Hillary sustained snipper fire.