Waypoints are saved in the unit's memory. Snapshots are written directly to a memory card.
Not related in any way other than a snapshot is a picture file and along with it on the memory card is a location file that will display a thumbnail snapshot on the chart view when you are at the waypoint.
If you did not Export all your waypoints to the memory card, you don't have them. They are never written directly to a memory card when saved.
Humminbird Helix 12 CHIRP SI, 1198c SI, 1198c SI, ONIX 10 SI NT, Helix 7 CHIRP SI GPS G2, SOLIX 12 SI, 360, RC-1