It's hard to confuse Jim Cramer when it comes to Wall Street, but he told his "RealMoney" radio show listeners on Friday that recent stock market action has him stumped, because people are buying stocks that are up huge. "Every morning, the market opens nicely and comes crashing down," he said, and that means someone is taking a beating. There are markets when you literally have to buy the opening every day because the early trading is always bad, he said, using the 1990s as an example. That's when the Japanese were constantly dumping U.S. stocks as the country struggled with what Cramer called "the greatest bear market of all time." Europe was also weak at the time because of Russia, he said, so every day it made sense to put money to work at the open. Moreover, he said, there are openings that are mixed and investors pick and choose. But this stock market "does not reward you for buying stocks up in the morning," Cramer said. "You've got to fade this market, which means you've got to bet against it (in the morning)," he said. In addition to accepting opening prices, investors are also using market orders instead of limit orders. So, what do you do if you do fall in love with a stock? Curb that instinct to buy at the open, Cramer said. He said he would wait until 10 a.m. ET before taking any action, and then he would only buy one-quarter of the order he wants. You want 200 shares of Motorola ( MOT)? Cramer said he'd buy 50 to preserve his capital. Almost every day, Cramer said, he sees opportunities to buy stocks at a discount because sloppy sellers come in and unload companies they should hold on to.