What keeps "loose lay" vinyl plank flooring in place? It's advertised as no-interlocking and not glued except at the perimeter if there is no wall bordering it. They say that when you move, you can take the floor with you. For example: https://www.youtube.com/watch?v=pbySUjCH6-s
The only samples of loose lay flooring I can find locally are attached to display boards, so I can't see what the back of planks is like.