Handedness question for youth hockey players

My sons (6 and 4) are in their first year on an in-house team and really enjoying it. Hockey wasn't an option for me growing up, so while I love the sport I never played aside from in the driveway.

Both boys are right handed for everything. I noticed when they're sprinting they both hold the butt of the stick with their right hand, but when they go to shoot they'll switch hands to move their dominant hand to the bottom for a righty shot. Likely a factor in this, they were both introduced to baseball this past year.

What's the best way to correct this? Should I let them keep shooting from the right and encourage them to carry with their left, or focus on helping them develop a lefty shot?