People oftentimes feel being taken advantage off, and to me it's because they allow it to happen or because they aren't skilful in staggering "being helpful".
For instance, if you were to bring me coffee every morning, I'll naturally would expect coffee from you and it must meet the taste that I'm accustomed to. Sometimes I might even gently reprimand you for being late or buying the wrong type.
But if you were to buy me coffee sparingly, on certain occasions, I'd most certainly appreciate it and would thank you graciously.
Does this make sense?