The reference is on page eight, second column, first paragraph, last sentence. "When you have to choose from a list of bonus feats in your second class, you can also (emphasis mine) choose from the bonus epic feats described for each specific class below." The word "also" strongly implies that you would ordinarily not have access to the epic feat list, which specifically means non-epic levels. So a Wiz20/Ftr1 could, for example, pick up Epic Prowess as his first Fighter bonus feat.
Having said that, play it in whatever way you want. I personally see nothing overpowered about it either way.