NEW YORK (TheStreet) -- Retail sales dropped unexpectedly for the first time in eight months in May, data that will likely reignite investor fears that a consumer recovery remains tepid and reinforcing the possibility of a double dip. The Commerce Department said Friday that sales for the month tumbled 1.2%, even as economists forecast a 0.2% gain. This follows a 0.6% increase in April. This is the first decline in retail sales since September 2009, when they tanked 2.2%. On a year-over-year basis, sales grew 6.9%. Sales were particularly hurt by hardware stores, auto dealers, gas stations, department and clothing...