Why do you ride on my boat?

Hey,I am a boatman.
You may treat me as worthless one.
You always neglect me but you are fit.
I am not an educated like you
So,I don't know how to conceit.
I have red blood.
But you have blue,
That's why you
Insult me without any clue.
I haven't got from you
A smiley moment for a few..
My skin is black,you are white.
My dress is dirty,you are clean.
My speech is bad,you are an awesome speaker.
My song is boring,you are a lovely singer.
I am illiterate,you are all knowing person.
You call me vulgar fellow,I call you sir.
With due respect, I wanna ask you
Why do you ride on my boat?