I never feel any guilt about taking things from the trash. About trespassing to somewhere you're not supposed to be? Sure. But if it's something that's 100% clear is in the trash and will be going to the landfill and not going to some charity reuse place or something, and I want it, I'm taking it.
When I find people recycling out of our trash bins I just remind them that I have to ask them to leave because it's a liability issue. Then I let them know what our office hours actually are.
Depends on the trash. A co-worker and I would regularly grab prototype machines out of our dumpster. Thousands of dollars of quality electromechanical hardware (motors, precision linear slides, pneumatic cylinders, mini-compressors & solenoid valves, etc.) and big sheets of 6061 aluminum for the taking. Company had to throw it out and tell us not to take back out in order to take the write off.
At one point we upgraded to having an intern standing in the dumpster throwing stuff out to us as we directed him.
I never feel any guilt about taking things from the trash. About trespassing to somewhere you're not supposed to be? Sure. But if it's something that's 100% clear is in the trash and will be going to the landfill and not going to some charity reuse place or something, and I want it, I'm taking it.