Why do entities stack? If this is intentional, can it at least be configurable?

Expected Behavior

Entities to be placed on the ground next to the existing one

Actual Behavior

Entities stack if you accidently click on their hitbox

Steps to Reproduce

Make a pen
Fill it with pigs
Try to put another one it
It will be almost impossible to not have it stack on an existing pig

Version of Minecraft, Carry On, Forge/Fabric

Forge 1.18

Not sure about Forge 1.18, but on 1.19 versions we have lots of config options to alter stacking, such as maxEntityStackLimit to specify how many entities can be stacked at once, useWhitelistStacking + allowedStacking to let only whitelisted entities stack, stackableEntities can disable the feature altogether, entitySizeMattersStacking defines whether the size of the entity matters and forbiddenStacking lets you blacklist mobs without using a whitelist. All of these are located in carryon-common.json

It appears to have world specific config files. Thanks. Perhaps it should be off by default?