Shake Shake’s shares tumbled 30% on Thursday after it blamed disappointing financial results on bad weather, high beef prices and tourism declines. The Big Apple-based burger chain missed Wall Street’s estimates for sales and profits in the quarter ended April 1, losing $290,000 compared to last year when it posted a $4.25 million profit. Revenues rose by 14.3% to $367 million, but Wall Street had expected $371 million.  Bitter cold and rainy weather in January and March kept diners away,