Humans are generally trusting creatures, from the day we were born we learned to live by putting our trust to people who take care of us. Unknowingly a baby learns how to survive depending on who they are with and with that in mind people grow up.

Whether a human was pampered or not you can still manipulate them, its just the effort it takes to gain their confidence in you which is hard but by gaining their trust and after that you can basically have them do anything depending on how deep your connection with them is.