That's pretty good point actually. So if we would find out that there really isn't more that motivate people, we should focus on pride, sloth and lust, since they are environment friendly. Pride is kinda the same thing we talked about respect earlier.
Except that these are only the negative sides. The ideal communism was inspired by was most likely a family. Extended family working together for a better life for all. This is a positive emotion. It did fail as a system, but some communes might have been working all right, who knows. There must be more positives except the want to protect your loved ones.