She sounds like a pretty nosy little chippie to me, you should have told her to go spear her own fish. Or tell her you are a HD cart consultant and your consultation fees are $200/hr against a $500 retainer. Or at least tell her she was standing in a customer area and she would have to move. Or “no habla ingles…”
 
She could have been an innocent ditz, or she could be just posing as such from the taxation dept (believe me, I have seen lower stings setting up at antique shows by undercover state officials), or maybe just casing out your biz so her dude can roll up and jack your earnings.
No, you are not out of line for being annoyed by someone asking for a free map to the happy hunting grounds.

When someone asks how much money I make, I tell them it’s under a $1000.00 most days.
Jerry

When someone asks how much money I make, I tell them it’s under a $1000.00 most days.
Jerry

I write the web address of this place down on a one of our business cards or on a piece of paper and tell them “this is where to go to ask all kinds of questions”.  Some of them know about it, others don’t.  I gave the address to an Italian Ice set up at a festival a few weeks ago… and they had already found this place.  David will tell folks pretty much anything.  He always tells the HD guy that he’s not selling anything (sometimes he’s right!)…  Our current HD guy drives by almost every day…. don’t you just love small towns!

Nothing new about this, any one who has a successful vending business, can expect to be aproached like this from time to time.  After a while it gets old I know, but it is part of the business we chose.
As the economy gets worse it will happen more and more frequently.  The situation this presents is one of the dirty little open secrets of our vending business.   We all want to help, thats why we are on this forum, but there is a limit noobs don’t understand.  I will be glad to help, but I’m not going to help you, make my life harder. 
 
Give them the RF IP.  Or get a contract, 20 percent of their profits, and put them in business across town.  

Those answers really made me laugh!!
 
I have thought about asking Vendors some questions, as i am only THINKING of getting started in the business. But those questions she asked were somewhat inappropriate!  Hopping out of the car and asking a ton of questions without buying something is mega-rude! I would never ask someone what they make, as some people get really offended by that question….If you are going to be in a business that deals directly with A LOT of people, then TACT should be used!