So the shot prevents sperm production, causes acne and mood disorders... so it makes you female?

Allergies are not genetic. The predisposition to develop them is.

You got lucky with your saleman. You're expecting them to know what they're talking about? That's setting the bar a little high. People really should just read the manual when they get a new car... No, that's setting the bar even higher, sorry. When I bought my Prius, the salesman said that "if you're battery is getting low, just pull the transmission lever into B and hold it there. The B stands for Battery!" Of course it's actually the engine braking mode (which may resut in some small battery gain) and doesn't need to be held down, but they just make up whatever to make the sale. Don't reward ignorance. Either exploit it for a discount, or don't buy from them.

If you sell someone a product, you don't get to follow them home and monitor their use of it. If they reverse engineer it, good for them. If they reproduce it, good for them. If they distribute or sell their reproductions, sue them. You can't prevent all your customers from using what they bought just to make sure none of them misuse it.

It's like selling a sandwich and requiring the buyer to agree not to open it to see what it's made of, and then following them home to make sure they don't open it because you're afraid they might learn how to make it themselves and post the recipe online along with *GASP* a picture of the sandwich! It doesn't matter that they told everyone that you made the sandwich, not them. It doesn't matter that this free publicity drew hundreds of new customers to your little sandwich shop. No, you're a paranoid control freak who thinks his sandwich sales will drop because people can get the recipe online, even though there's no evidence supporting this. In fact, you're considering selling the sandwich in locked lucite boxes that only expose the sandwich one bite at a time, and while you're at it, why don't you collect information on sandwich usage, kitchen appliances, travel habits, and social security numbers? All this security is costing so much, the sandwiches that should cost about $2.25 now cost about $19.95.

And now you're wondering why you're being outsold by those unprotected sandwich shops charging $2.25.