I kinda like this.

I don't know whether wiping one's sweat from a gym machine helps limit the spread of sickness, or if it is basically a matter of eliminating yucky-ness. If the former, I'd say sticking with the current norm is better, and I might even suggest a "wipe down before AND after your use" rule of thumb. If the latter, I'd say an update along the lines you suggest is at least reasonable to consider, as individual tolerance for yucky-ness of this type is quite subjective. It's just sweat...