It needs oil. Oil will break down the adhesive and shouldn't be hard to clean off of a sealed/finished surface. I've used anything from a few drops of cooking oil to peanut butter (doesn't run!) and let it sit. Depending on the adhesive it could take minutes or hours, but typically makes removal much easier.
Make sure to use a solvent that damages that surface. Easy peel stickers are apparently yet to be developed.
I feel for this one. This is such a stupid common thing. I also hate the thing where packaging was made more difficult to discourage returns but that thankfully has at least reduced from its height.