I disagree. If OP is truly selling a 'dream', as this user suggested, then it could prove to be profitable.
If you could compile a (fictitious or otherwise) list of customers/people who have found treasure in their yard, then people could be persuaded into giving it a go. Real people would be better, but they hardly exist, and their discovery may have taken place YEARS ago.
Obviously this all depends heavily on your sales skill, but if you could pull this off... $.
People are more willing to spend money when they can be persuaded into thinking of it as an investment. I went to China some time ago on a tour (which are known for bringing you places that offers them significant sales commissions).
Anyway, a more memorable part of the tour involved the tour guide telling us about a previous tour member who had struck it rich buying a certain art piece. She painted a story involving this person going into a pottery studio, picking out a random piece that he thought looked nice, and obviously it was one that was painted by the Chinese version of an Old Master figure, netting him hundreds of thousands in profit (gross simplification of story).
When we got there, most of the tour members were snapping up pieces. I won't lie, I was also affected by the story and was trying to find a good piece, anything significantly different. These pieces were sold at a slight premium (something like a couple hundred bucks, nothing people couldn't afford), but their true value was obviously a lot lower. I snapped out of it only because my father warned that I was getting too affected by the story, but everyone else were buying pieces left and right.
A dream, friend, is something a lot of people will pay a lot of money for. Even if they know that the chances of even breaking even is next to nil, they will buy it to just ENTERTAIN the mere thought of getting rich. Ergo for lottery tickts.
I have more... observations,if anyone's interested.