Preheat your grill to medium-high heat.
In a large bowl, toss the cut fries with olive oil, garlic powder, onion powder, paprika, salt, and pepper until evenly coated.
Cut two large pieces of aluminum foil, about 18 inches long. Divide the seasoned fries evenly between the two pieces of foil.
Fold the foil over the fries, sealing the edges tightly to create a packet.
Place the foil packets on the grill and cook for about 20-25 minutes, turning occasionally, until the fries are tender and crispy.
Carefully open the foil packets and sprinkle the shredded cheddar cheese and bacon bits (if using) over the fries. Close the packets again and grill for an additional 5 minutes, or until the cheese is melted.
Remove the packets from the grill, open them carefully to avoid steam, and garnish with sliced green onions before serving.