Sure, you can use Miracle 911. But the big problem isn't staining. It's etching. Concrete is alkaline, and when exposed to acids like soda or citrus, that will actually eat the surface away. Penetrating sealers don't protect against etches. Film forming sealers---a layer on the surface---can protect against both stains and etches. But, putting plastic on top of your counters kinda defeats the whole purpose! It's like your great grandmother's living room with the plastic covered sofa that no one ever lived in!

Embrace the patina! Every single stain or etch proves that you've enjoyed using your kitchen! They are badges of honor. The more broken in it gets, the better it reflects your personality and the life you've LIVED in your home. Just like a pair of great jeans. They fit the best when they're just about worn to death.