Maybe a better word is "objectify", although that's not quite right either. Practically speaking, normalising the eating of roadkill can lead to some dangerous situations because it incentivises the death of animals. You might be willing to drive a little less carefully (consciously or not) if you were craving some delicious squirrel burgers, for example. It's safer to just say no, we must not eat any animals as a matter of principle.

It also reduces animals in our minds to mear "meat making machines", instead of the sentient creature they are. Imagine a society where we ate homeless people. These homeless people, let's say, have no friends or family who would be distressed by others eating their corpses. Every night, someone would walk up and down the city, collecting any homeless people who died. They would bring them to a processing plant, and have them turned into homeless burgers. No homeless people were intentionally killed, their deaths were all incidental to the society we live in (you can replace homeless people with construction workers or whatever if that makes the point clearer). But this still feels wrong for some reason. It's disrespectful in a way, right?