talking about pulled from a listing I saw recently:

"The commission payable by the OWNER/LANDLORD to BROKER shall be a total of Five percent (5 %) of the Total Sales Price of PROPERTY, payable through Escrow at the close thereof. OWNER/LANDLORD acknowledges that Broker is entitled and encouraged to solicit the cooperation of other real estate brokers. However, BROKER may not enter into any commission agreements with other brokers that would be inconsistent with the terms of this AGREEMENT or which would increase the total amount of OWNER’S liability hereunder, and OWNER’S sole liability for commissions shall be as provided in this AGREEMENT. BROKER has no responsibility to pay a fee or commission to a cooperating broker, unless and until OWNER/LANDLORD has paid the fee or commission to BROKER."

Nowhere does it specify x% to seller's broker and x% to buyer's broker. Just a flat percentage which can be shared with the buyer's agent. If there is similar language in the listing agreement of the property the OP is trying to buy then his offer is not $20,000 better than others because he is unrepresented. The fact that he is unrepresented would make no difference to the seller. If that is the case he is essentially hoping the listing agreement would agree to a lower fee because he doesn't have to share it with a buyer's broker. Now I am making an assumption about how the listing agreement is worded, but nearly ever listing I have ever seen is worded similarly to this.