Quick formatting and repartitioning simply gets rid of the areas of the drive which describe how the data is stored, not the data itself. There are utilities that can scan through the drive and recover things that are not in the file table. If you do a full format (not a quick format), then yes, the average person will not be able to get the data back because it should all have been set to 0s. The government can still get data off of it, because there is still some residual magnetic signal left from the previous write, and if you know that every byte has been overwritten with a 0, and if you have the facilities, you can recover the data. If you really need to hide something from big brother, you overwrite the drive with random bits.
That's a lot of trouble someone would have gone through just to see a bunch of pictures of my animals running around :~)