I'm sorry but what is the point on this. Is this a way of conning people into making graphics, selling them and sharing the money with you? Why? They could quite happily make their own shop and receive 100% of total sales.

If you are, at least change the percentage of overall sales to...
30% Owner
70% Staff

...or something more suitable.

Sorry to P!$$ you off, I just wanted to make a point.