CTLAWYER,
We’ve always kept cleaning chemicals and bug chemicals, etc under lock and key.
It’s still an element of babyproofing, even if the original intent was senile-relative/non-English-speaking-help-proofing. I’m sure once you had young children in the house, their safety became part of the calculus for keeping those items away, despite the boundary setting and supervision.
Our kitchens are locked because we live in small town New England.
Yet your lead-off reason for locking the kitchen given above was “so no child…”, so obviously children were part of the equation here too, not just your non-Jewish houseguests.
Why do you find it problematic that someone might consider the safety measures you have taken in your home to be considered babyproofing?