If we're heating our plant up w/ greenhouse gases, polluting our air, hastening the extinction of certain animal species, melting the polar ice caps, and changing the sea levels, we're hurting our environment and those that other living organisms depend on. It's just happening in slow mo in comparison to, say, throwing trash out of the car window or spewing exhaust into someone's face.

Not sure why the OP didn't use the term "organisms" in place of "bacteria." Bacteria are fairly simple organisms. We're a lot more complex.