This is a question I have been asked multiple times in the past few months, so I thought I would share the general consensus amongst both home stagers and real estate agents:
Staging benefits the home owner the most, so the home owner is generally the one to pay for staging.
A recent example would be a potential client I met with who had just lowered their listing price by $15,000. It was my difficult task to explain to them that if they had spent $5000 on staging, they probably could have gotten their original asking price or more. In this case, the seller would have benefitted by $10k or so more in their pocket, whereas the typical agent would have benefitted by only about $450 (3% of the $15K).
In some instances when the result will be highly dramatic, the real estate agent will pay for the initial consult and assign it to their marketing budget. According to my Marketing 101 college professor, marketing is "finding out what the customer wants and then giving it to them". What else is home staging if not marketing?!
Let me explain another reason why I don't really encourage real estate agents to pay for the staging services of their clients in full: if the seller isn't "sold" on the service, they will move the staging back after it's done. Why not move it back? There is no investment in the service.
These before and photos are from an amazing transformation and currently available property in the Park Cities area:
And here are staging photos of a current listing in Sunnyvale: