Living in Peace Side by Side

This is the scene just outside my office building, a FedEx drop box and a UPS drop box. Mortal enemies they be, yet in peace do they sit side by side.

Pray tell, then, why can't we humans do the same? Why must we always be in disharmony?

Perhaps the secret is in the timing. The FedEx rep comes at 6:30 pm according to the box while the UPS rep comes at 7:00 pm. Sometimes to keep the peace, messengers must be kept separated.