These sort of conversations only happen when the "business" person is looking to sell you something not buy. After many years I have learnt to ignore them.
I've had all of these circumstances in the last 1 year.
By ignoring requests to talk because your world view consists of a negative outcome from almost any kind of unsolicited contact, you're cutting yourself off from a lot of opportunities.
Perhaps they're planning to dump some employees and replace them with you, or dump their current provider IF you work out at the meeting. That's the absolute best case.
Worst case is you can expect loads of BS about the undocumented verbal meeting "well, at the (carefully undocumented) meeting you agreed verbally to 25% off regular price and (insert list of features) all available within 72 hours, so ..."
I always use my iPad for just such situations........ I've learnt over the years that while others may want meetings undocumented its best to ensure you have comprehensive notes.
Then a few days goes by and the customer buys our product and it very clearly states in the contract that 15 things will be done by yesterday even though it will take a good 100 hours to fix and the customer doesn't have to pay a dime, because it's "evolving the product".