Green screens (and blue screens) are not a simple thing to master. The color must be a very specific hue to work well, and even lighting is critical, using lights of a specific color temperature.

For most product photos a better alternative for dropping out backgrounds, at least for print or web images, is a white screen with a lot of light pointed at it, but moved back from the product so it doesn't rear light the object. That way the background washes away into pure white.