I'm surprised that you felt that selling things via FBA is scammy. I have a full-time job but I also own a business that (currently) grosses about $150K on Amazon. I can honestly say that I don't feel like we've out-manipulated anyone or have done anything but create a very competitive product that we're able to sell at a competitive price.
I agree that it quickly turns into a very painful race to the bottom when dozens of vendors are selling variations of the thing (e.g. silicone grill gloves or meat claws), but it's completely different when you're able to take the time to create a really great product. It's been a rewarding experience; I highly recommend it to anyone who doesn't mind answering the occasional support email and is completely committed to excellent customer service.