Dropping multiple blocks in Minecraft make all items come to one. How to stop this?

I'm making a payment system but noticed that the gold weighted pressure plate will give a low signal because all the items form into one when thrown near each other. By the way, I have a Macbook Air 2011, help would be appreciated!

They become one stack on the ground if they are thrown near each other. There's not a way to stop this, it is part of minecraft.