I think these spawn beacons are hindrance to the flow of the battle and create chaos by diminishing what should be a clear battle front-lines.
It allows players to easily and repeatedly spawn behind front lines, thus eliminating any order of battle and turning the battle style to a team death match since the players don’t know which direction the enemy is coming from! This confusion creates chaos and loss of cooperative teamwork. Everybody will be heading in different direction with no sense of battle flow. Everyone does not move as a army, they move as random soldiers going in all directions.