If you can do a thing ethically, calling your act an experiment, or paying attention to how people react, doesn't create an additional ethical burden.

It doesn't follow that if doing X doesn't make anyone worse off, we should allow X. This fails to consider the impact of incentives. It may be that if we permit X, X would be better for everyone in the current situation, but permitting X also affects the balance of what situations exist to begin with, leading to everyone being worse off overall.