My favorite opening book is Understanding the Chess Openings by Sam Collins. While not as detailed as FCO, its easier to read. I always go to the Collins book first.
Good but more detailed are the series of four books by Stefan Djuric et al Chess Opening Essentials Vol one is 1 e4 openings, Vol 2 is 1 d4 d5 and Vol 3 Indian Openings. Fairly explanatory, more detail than FCO, but in double-algebraic (sometimes called full-algebraic) notation.
To put it another way -- just as people are crazy for tactics these days so that they don't have to think about how to trap a loose piece, they simply recognize the pattern and do it, I assume the pros must be functioning at that level with openings too, to save time on the clock if nothing else.
As to getting the general story of an opening -- White attacks on the kingside, Black looks for a d5 break, the dark squares are weak but there is compensation on the half-open c-file etc. -- I'm sure the pros know those stories for all openings and major variations whether they use them or not.