Maplebear Inc. (NASDAQ:CART), operating as Instacart, saw its shares decline on Friday after research highlighted topline risks associated with rising competition in online grocery delivery.Piper Sandler downgraded Instacart to Neutral from Overweight, lowering its price forecast to $41 from$62. The firm's updated six-year DCF assumes a 12% discount rate and 2% terminal growth.Piper Sandler analysts led by Thomas Champion said heightened competition in the digital grocery sector puts pressure on Instacart' ...