I developed over the past couple of months a tool for simulating embedded systems. I'm at a point where I could go to potential customers and demonstrate the product, however I do not have any real-world use cases to show them yet, only hobby-level small projects that I created with the tool. How can I get around this chicken and egg problem of finding a first customer to sell to while not having any industrial use cases?
You need to come up with something that works before you can expect someone to pay. Why would someone pay money sight unseen for something? They don't know you and they don't know if you will even finish what they paid for.
Show it first to people you know in the industry and ask them about how they would use it. Get some good use cases from them to demo. Better still, ask them to try it for free and give you feedback. You can't do it with strangers so stick to your friends or FoF.
Tanking a product that you think is half-baked to real prospects is a recipe for disaster.