Chickens start eating their eggs when the shell is so soft it breaks easily. When they get a taste for it they almost do it as if addicted to it.
I had chickens once that would hover around the nest box waiting for a chook to lay to see who could be the first to get to the egg.
Then one day...
Get an End cap and cut half of the inside of it out so you are left with only a half moon hole put this over the end of the feeder to reduce opening size. This might stop wastage.
Also to help stop clogging use a 45 degree angle half way down the main feeder pipe to angle it, the change in...