Depends on your pay plan but someone with a nice fat book of business and continuing plan to expand said book of business could negotiate a very generous pay plan as well as the budget for a few assistants to help with the volume.
Some things are more important than money and I sleep better at night providing a service for a fair price rather than squeezing folks for every dollar.
This is true for all the usual NYC/LI/NJ based retail brokerages which I’m sure are the people you’ve had the most experience with, but not of most of the ones here, myself included. I don’t make a penny more if I sell for invoice or 2k below, we make our fee and that’s it.