They do make dutch ovens without legs.

If you want to use them over a fire or over coals you just use a trivet under them or hang them from a tripod by the bail.
If you want to stack a few of them and use coals between them you can set them up on steel trivets there too.

Because they are flat bottomed they will work on a stove or in an oven. They work off the fire just like a big heavy cast iron pot, which is all a dutch oven really is if you think about it.

More important to have than the legs is the rimmed lid so you can pile coals on top of the dutch oven, but I have seen them with lids that were not rimmed and they still were workable.
Not as nice to use, but workable.

You should make sure you have something you gan handle the lid with. A large pair of water pump pliers or a specially bent rod. The rod doubles as a poker for the fire.
You don't want to be burning yourself handling the lids with coals on them..