Dave & Buster's Entertainment Inc (NASDAQ:PLAY) is plummeting before the open, down 19% to trade at $9.98, after the restaurant and arcade operator reported weaker-than-expected first-quarter results. The company earned 22 cents per share, missing analysts' expectations of 37 cents per share, while revenue of $559.2 million missed estimates of $580.5 million. Comparable-store sales fell 5.4% year over year as well. In response, Benchmark downgraded the stock to "hold" from "buy," while BMO cut its price tar ...