Little Rock Nine documentary response

After watching the Little Rock Nine documentary all I could think was "wow, how could someone be strong enough to deal with that kind of hate day after day".  I knew about these events prior to seeing the documentary, but for the first time instead of just looking at the nine black kids entering the school and the history they were making,  I also paid attention to the things the white people were saying and doing.  They were saying extremely hateful things for no reason, beating them up  It's hard to wrap my mind around the fact that a person can hate another person for no reason.