I'm not an expert, either, but I believe that animal cells are different from most other living things (plants, fungi and fungus-like/bacteria and bacteria-like

I'm not an expert, either, but I believe that animal cells are different from most other living things (plants, fungi and fungus-like/bacteria and bacteria-like organisms) in that they do not have cell walls, just a flexible, self-healing membrane. Organisms with cell walls often have internal pressure, which makes any punctures much more serious than for animal cells. Perhaps something like that is in play. I do know that a common mechanism of action for many common antibiotics is interfering with the formation of cell walls. That's what lets them be effective against bacteria without causing (much) harm to the surrounding animal cells.