I have added the assembly instructions to the information. It is not absolutely necessary to mount the feet. The sideboard can also simply be placed on the floor.

Yes, you don't necessarily have to mount the legs.

In my case, the feet were simply left out, although they were exactly the reason for the sideboard (I wanted a highboard). I have now been waiting 9 weeks for the missing parts (the sliding doors were also not delivered). So you can assume that individual parts will be missing on delivery - maybe you'll be lucky and it will be the feet.