I am of many colors;
People need me;
At the end of the day, I am short;
I do not cost much;
What am I?
Chalk!
Light?
Change.
Colour changes
People always need change
Most are short on change at the end of the day
and change isn’t worth much (i.e. a penny is just worth a penny)
Did I get it?
The One Ring!
You’ve got it in your pocketsssssss, doesn’t sssshe, my Precioussss?
I’ve been spending too much time in the basement lately, haven’t I?
chapstick?
A candle?
Temper.
I think it’s something like chalk, lip-stick, lip-gloss, or one of those that have many colors and are shortened from use and are cheap.
IT JUST SEEMS TOO OBVIOUS. Does anyone know the real answer? Has anyone heard this one before?
There aren’t enough details given to name a specific answer. You could come up with any number of plausible responses, as people in this thread have done.
The riddle doesn’t even ryhme or have any poetic value at all.
A prostitute?
Can you provide us with some context, such as, where did you pick up this riddle; how old is it; what part of the world does originate in?
A raven! No, wait…a writing desk!
waitress - maybe short means “short tempered”
The word SHORT.
But who needs short? 
I think Scarlett67 got it:
light
right, light is actually all the colors together, people need light, at the end of the day there’s no more light so I guess you could say it’s short, and it doesn’t cost much…I guess
but of course it could be a rainbow
…everybody needs a rainbow!
Blue! No, green! AAUHHHGH!
pro-bono Munchkinland civil rights lawyers?
No?
OK
I prefer The Edge, personally…