According to the United States Department of Agriculture pumpkins are grown and harvested for two main reasons, seasonal foods and decoration. In a USDA report released in 2006 that 1.09 billion pounds of pumpkins were harvested in 2005.
The "better practice" would be to build a stable economy in your local area. This is done by purchasing food, goods and even pumpkins from local suppliers, farmers and manufacturers. If you are purchasing your pumpkin from a local grocery store, ask where their pumpkins were purchased.
On a side note, if you have young kids or just love to get outside during the fall months, turn the buying experience into a day trip. Visit a local pumpkin farm which offers hay rides to the pumpkin patch where you can pick your own perfect pumpkin, and end the day with a cool glass of apple cider and spice donuts.
Happy Pumpkin Hunting