Reloading grenades after every death/respawn turns this game into a Grenade fest which is annoying. Everyone should start out with two grenades, but after they use them they should not automatically get them back after they respawn. Every grenade after you use the ones you start out with should be earned throughout the map.
welcome to halo. Its always been like this and realistically, not spawning with nades would not effect much given how many are on the map. Players will ALWAYS have nades. Its up to you to learn how to dodge them (big thing is basically never back peddle unless the nade lands in front of you)