You would think that with Apple riding high in the stock market, investors would be breaking out the champagne and celebrating. Unfortunately, with the holiday quarter financial results coming on Tuesday, the sound of grumbling is what Cupertino is hearing instead.

The Wall Street Journal is reporting that some Apple stockholders are exactly bullish over how the company is hoarding cash these days -- some $50 billion right now, which is expected to swell to $70 billion by the end of the year. According to WSJ, that sum “exceeds the gross domestic product of two-thirds of the world’s countries.”

Despite sitting on a veritable mountain of greenbacks, Apple is playing Scrooge when it comes to spreading that wealth to shareholders via dividends or buybacks -- instead, Cupertino is keeping the money close to home, offering only “dismissive koans about possible acquisitions and the need to remain flexible and conservative.”

That conservatism has outraged shareholders like Christopher Bonavico, who oversees $700 million in Apple stock at Delaware Investments. While Bonavico raves about Apple, he claims the company “is destroying value” by holding tight to the cash, even as he claims that Cupertino is undervalued by as much as 30 percent.

"We absolutely love the product strategy,” Bonavico gushes. “However, they are leaving money on the table by having such a large cash balance well below their cost of capital. The cash is earning near zero."

Of course, few shareholders are as vocal as Bonavico, the portfolio manager at Delaware’s Focus Growth team. With Apple’s stock price riding high, most are content with seeing their shares rise nearly three times since the market tumbled in March, 2009 -- but questions about the company’s cash hoarding threaten to swell to a crescendo over time.

"I think it has been beyond the point of being rational for a while now," claims Bernstein Research analyst Toni Sacconaghi, claiming that even a $15 billion acquisition of a company like Netflix could easily be financed, thereby leaving plenty of buybacks or dividends for all.

Apple will announce their fiscal year 2011 fourth-quarter financial results on Tuesday, on the heels of CEO Steve Jobs’ announcement Monday that he will be taking a medical leave of unknown duration.

Follow this article’s author, J.R. Bookwalter on Twitter

(Image courtesy of The Wall Street Journal)