Thank you Mr. and Mrs. Seller for asking such a wonderful question. I get asked this all the time when visiting sellers. Mainly, the concern is "why should I use you when I can get a cheaper commission with your competitor?". Though the answer is based upon individual circumstances. I will try to answer this to fit all.
Some of the larger brokerages do not allow commissions to be reduced because the services offered are unmatchable and high quality. With proven track records and producing higher list to sold prices, there is no reason to reduce a fee that has to cover the cost of doing business.
Many of the smaller brokerages reduce fees to get more business to cover their cost of doing business. They offer limited marketing, marketing of lesser quality and offer less services. Which typically means that your DAYS ON MARKET IS LONGER and you typically receive a lesser sold price (the $$ in your pocket).
A broker that only charges to list your property (Limited Service) only does just that. You are given no service at all. Kinda like walking up to a coffee bar and making your own coffee versus going to Starbuck and ordering to your specifications. Or going to the coin carwash and washing your own car for 2 hours versus driving into a carwash to have them clean and detail your car in 20 minutes. You get what you pay for.
Selling your home is the BIGGEST DOLLAR TRANSACTION you will ever have. Get the best representation, get the best advice, get the best service, get the best marketing and get the best price for selling your home. Pay for what you want and you will have more $$ in your pocket!!