Hmmm, why can't battle be conducted as it is in other games (without minis and visual references)? Sorry, I haven't gotten to reading most of the book yet, so I'm sure I'll find the answer then, but is combat SO tactical that you must have minis or markers to keep track of it all? That would sadden me.
That's the way d20 has been designed, to be more of tactical miniatures wargame. WoTC did this to sell miniatures and wargame rules, eating into the market held by Heroclix, Warhammer, MageKnight, etc. The tactical nature is a blessing (for those who have minis and a desire to get tactical) and a curse (for those who don't).
I have around 500+ minis (most finally painted!), a $50 dry erase battle map (hexes on one side, squares on the other), and a bunch of mounted full color Hero Quest tile "battle boards" which I got free online (cut and combined and mounted myself, so now I have gridded forests, inns, taverns, temples, crypts, pirate ships, sewers, secret bases, etc.).
You can get free gridded tiles pull-outs in certain back issues of Dragon magazine, and you can buy cheap pre-painted plastic minis or cardboard counters in game stores.