At a recent conference, one of the things the co-ordinators asked was that everyone bring their unused soaps/shampoos/toiletries from the hotels they were staying in. At the end of the conference, the co-ordinators donated all of the toiletries to a shelter.
So, in the morning, before you leave your hotel to attend the awesomeness that us Steemfest, grab all of your unused toiletries and bring them to the conference.
If you think this is a good idea, then help make it happen.