It sounds like your being selfish, as only one who is selfish would not admit to partaking in the squandering of our children's inheritance. I do not claim to be not guilty of this crime, but I do claim to do my best at being efficient and being non-wasteful as soon as I can. Unlike some people, I can admit that I make mistakes, that I am human. Simply because one is guilty of making poor decisions does not make that decision any less poor.
Am I saying you should "feel guilty about using a particular light-bulb"? Certainly not as guilty as depleting the earth natural resources by not supporting the cause to stop using non-renewable resources. If you're not for getting off using non-renewable resources, you are against it.
Denial is the first sign of guilt and a sign of immaturity. One who cannot see their shortcomings, cannot handle the possibility that they are imperfect. The sooner people own up to their mistakes, the sooner we as a race will make progress. Denial of imperfection is pitiful and reflects poorly; it is this way because it is so very clear that no one is able to be perfect and denial of that appears bullheaded.
Simply because you feel helpless in a situation, does not require you to distort your beliefs to better serve your ego, i.e. some may say: "there's nothing I can do about it so I will just say there's nothing wrong with it".
Let me ask you .. if everyone in society jumped off a bridge .. would you do that too? Using your logic, if everyone started murdering people, it would be O.K. because "virtually everyone" is guilty of it. Your reasoning holds no water. It just looks more like a cop-out than anything.