If you want to shoot fairly small object from above a copystand is far more convenient than a tripod.
I'm also a coin collector so it shouldn't come as a shock that I like to photograph coins. Sometimes the coin is simply loose, but often it's in a cardboard or plastic holder of various sorts. To put it simply, it's a heck of a lot easier to put a flat coin on a horizontal surface than to rig up ways to hold it vertically without having the coin tumble at the slightest bit of clumsiness or having the support block part of the coin.
So let's say I want to photograph a shilling that is 24mm in diameter. I want to have it fill as much of the frame as possible. These days, I typically use my D800 and a 105mm VR for this task, which means shooting at close to a 1:1 magnification. The end of the lens needs to be about 15cm from the coin and the camera body about twice that.
You can work out the mechanics of doing that with a tripod. Or you can take my word for it, even when you mount the camera underneath the tripod on a geared center column it's not fun. One typically ends up in the middle of a room with the camera rig (and possibly a focusing rail) hung off the side of a tripod head. You then kneel down (deftly avoiding tripping over light holders, cords, and splayed out legs), compose by tweaking shooting distance, focus and shoot.
With my copy stand, I swing out the light arms, mount the camera on the platform (using a shoe mounted bubble level), turn on the lights, lightly loosen a knob to allow the platform to move on a counterweighted column, compose, tighten the knob, focus and shoot. Varying the lighting is easy, and overall it's a far less precarious setup.
"There is no real magic in photography, just the sloppy intersection of physics and art." — Kirk Tuck