everybody's so tense...lol@the drama!
I dunno what U mean by "regular dirt" but im sure the shit from outside wouldnt be too safe to grow in unless U got rid of all the pest's, fungus, and mold in it. I also read somewhere that its best to sterilize the dirt by baking it in an oven for 2hrs and letting it dry prior to growing in it.
and as far as the water goes, if U dont let the water sit out then you might have some chlorine or other pollutant in your water that could potentially harm the plants...
so in theory, if you meet the required minimum conditions to grow then yes, you can grow something...but most growers are growing for quality, so we prefer our water and 'soil' (not DIRT) to be top notch...