Physics2D, Box Collider physics inaccuracy?

I am currently working on a game project and I have ran into issues with Physics2D, I am trying to have items in my game, these 2D items have 2D rigidbodies attached to them and 2D box colliders attached to them.

The issue I am running into is to do with gaps what are appearing between two objects.

I tried to illustrate the issue below

Is there a way to solve this issue? I have found similar threads with this issue, however i have never found a true solution to the problem.

You will notice, the bottom cans collide ( almost perfectly ) with the floor, however they intersect collisions with each other incorrectly. I had to make the box collider sizes SMALLER than the actual objects because this happens :

It seems like scale has an effect on why this happens, but is there a way that I can fix this? I can see that scale has at least some impact because the shelf collides better, which is at a larger scale than the cans.