Should I allow the seller's agent to "represent" me?

I made a cash offer (I'm the buyer, no agent) on a piece of land. I have done FSBO before and am good on the research there. However, when the seller's agent responded with a counter offer, they asked if they can put down that we are "represented" by them and said it does not change anything - no commission changes, etc. They said the seller has to pay the full commission anyway. Is there actually ANY sort difference? Any legal difference?

To clarify: I'm buying, no agent. They are selling, have an agent.