Chocolate Syrup in the grocery store is often located in the aisle with the canned goods are.
In some places the chocolate syrup may be located in the same aisle as the coffee and tea.
For example at the Dollar General in my area the chocolate syrup is in the same aisle as the coffee and tea is.
It can vary from store to store but most times the chocolate syrup will be in the aisles with the coffee, tea or canned goods.
In some grocery stores the chocolate syrup may also be located near the condiments or in the aisle with the sodas and canned tea.
If the chocolate syrup is not located in those aisles then it may also be near the ice cream cones, ice cream or other ice cream toppings or even near the peanut butter.
If you can't find the chocolate syrup or anything else you can ask a store associated or worker to help you find it or tell you where it is in their store.