Seller's agent requiring us to use her contract template

We were interested in putting in an offer for a house. After talking to the seller's agent, I mentioned that our attorney would be drafting our contract (as we're not using a buyer's agent for this purchase), and the agent told us "we're only accepting contracts using the (state NAR) template." She sent us a copy of the blank template and said her office would complete it with our specifics for our offer.

I've never seen this before, and it seems a bit suspect to me. My question is, is this a way for the seller's agent to capture the extra buyer's compensation being covered by the seller? I've bought before without using an agent and never heard of such a restriction on the contract template.

Edit: She just sent over the template. She prefilled it out to state that says I'll be using her colleague as my agent and asking to give them full 3%. This is after I told her I wasn't planning to use an agent. So I guess my suspicions were right...