Under the current structure of most real estate markets and MLS systems, the seller of the home is responsible for paying the buyer agents fees. In almost all cases, the seller will pay the buyer's agent a percentage, typically 3%, of the purchase price to the buyer's agent at closing.
This creates an inherent conflict of interest for the buyer's agent. The buyer wants to pay as little as possible for the home and the buyer's agent has a legal responsible to look out for this interest. However, the buyer agent gets paid more if the buyer pays more for the home. Therefore, while it is not in the buyer's best interest, it is in the buyer agent's financial interest for the buyer to pay a higher price for the home.
Buyers can avoid this inherent conflict of interest by hiring a firm like Flat Fee that rebates a portion of its commission to the buyer. Instead of the agent getting paid more as the price of the house goes up, the buyer simply gets a bigger rebate check from Flat Fee at closing.