There are people that we try to avoid, perhaps those who may have taunted, annoyed, or even mildly bullied us. If we find their lost ox or donkey, the last thing we want to do is to get involved and bring it to them. Still, the Torah commands us to perform Hashavat Aveida.
Similarly, if someone who hates me needs help loading and unloading his animals, I must role up my sleeves and work shoulder to shoulder with him to get his donkey up and running. (Based on Netziv 23:4,5)
These Mitzvot are not just to help out those in need, but also serve to train us to overcome our yetzer, and inculcate Midot Tovot.