There is no set standard for agent commissions, in fact commissions can be negotiated with any agent or brokerage.

Please keep in mind that the listing agent isn't receiving the entire 5% or 6% commission.

For example you work with an agent that agrees to charge 5% commission, they usually spilt that 50/50 with the buyer's agent, then (depending on the designated commission cut with their brokerage office) the agent has to spilt the 2.5% commission with their office. And on top of all the commission spilts...agent's commission pays for all the marketing and advertising of that property, and taxes are not taking out, so the agent has to put some aside for later.

Kathy,

Commissions are ALWAYS negotiable(usually between seller and listing agent) and 5% is common in my neck of the woods.
I'm obviously not in your area but it doesn't matter- there is no set commission.