it's not obviously serving non-domesticated animals to be cute. It hasn't historically stopped us from eating them at anywhere near the rates that would put that kind of pressure on.

If so, then it also doesn't significantly harm humans to see animals as cute (since it doesn't make us give up a source of food). If this is so, then a much weaker justification might be accepted for the source of cuteness, perhaps as weak as "side effect of phenotypically unrelated evolution".