If you want to play that game, Ted Williams had more homers than Ernie Banks and had 1700 fewer at bats. By your reasoning then, Banks shouldn't be in the Hall either.
Like it or not, Sandberg was one of the best at his position at batting and fielding. That is why he went to the Hall of Fame. If you deny Sandberg, you must also deny Joe Morgan.
If Sandberg gets you frosted up, take a look at Bill Mazeroski's numbers.
Ted didn't play infield. ;)
In any case, even if we stipulate that Williams was a better hitter than Banks - who can deny it? - it's also pretty clear that Ryno was nowhere near the hitter that Banks was. It's all about where you draw the line - if Williams > Banks > Sandberg, where should we draw the line for Hall of Famers? Personally, despite his fielding ability, I think Banks is clearly in, and Ryno's right on the cusp. You're of the opinion that Sandberg is clearly and obviously good enough, and I think he's kind of marginal. That's what's great about this country - I can have my opinion, and you can have yours, no matter how wrong you are ;)