I "left it out" because post players always shoot a higher percentage than outside players. That's expected.
Here are the game-by-game scoring totals:
Coppin -- 22-8
UNC Cent -- 22-9
Tex So -- 2-21
UK -- 14-23
UVA -- 9-15
Cham -- 11-24
Ark -- 18-9
Ariz -- 22-9
GW -- 20-15
ORU -- 14-10
Cinn -- 10-7
Sac St. -- 8-15
C. Ark -- 11-8
Mary ES -- 11-11
Tex A&M -- 17-13
Baylor -- 9-DNP
UT -- 18-3
Tex Tech -- 20-25
Each player's had one disastrous game -- Fitz scored 2 against Texas Southern, and David scored 3 against UT (after missing a game due to a death in the family, which might explain why he struggled upon his return).
Fitz has scored in double figures in 14 games; Davis has scored in double figures in 10 games (and remember, he missed one game and played badly in another after a death in the family). And four of Fitzgerald's double-figure outings have seen him score 10 or 11 points, which is a decent game but hardly counts as lighting it up (Cade's had one such game).
Fitzgerald's outscored Davis by five or more points in a given game six times, and Davis has outscored Fitzgerald by five or more points six times, too.
So even in this category, the disparity is not as great as you suggest, and when you add in turnovers, assists, rebounds, and fouls (especially fouls -- Coach Capel mentions Fitz's penchant for fouling virtually every time he meets the press) and then consider the leadership factor, one could quite easily decide that Cade's the team MVP at this point in the season.
As I said above, one can make an argument for Fitzgerald, too, but it would be based almost entirely on scoring, and he's currently besting Davis by less than one point a game. If he could manage to stay on the floor, he might widen that margin, but until he does (and until he improves his rebounding), I'd have to go with Cade. And I'll bet (though I don't pretend to know for certain) that Coach Capel would, too.