It saves money because it costs Marriott less to purchase bulk refills than small bottles. I doubt it has any significant effect on any single property's garbage bill. They probably still use the same number of dumpsters with the same number of pickups. I mean, really, all the bottles in all the rooms of a CY every day maybe fills one garbage bag?
In my post that you quoted, I stated that it's good for the environment - yet you accuse me and others of failing to see that? The point is, that if another new technology is invented for toiletries that saves Marriott even more money, they'll switch to that one, whether it's better or worse for the environment. The fact that they can claim this as environmentally friendly is a happy coincidence, and I don't fault them for taking the opportunity to get the good press. But large companies do this stuff to save money.
As one example of many I have in working with big corporations, I recall an executive telling me about an initiative to get rid of styrofoam coffee cups in the break room, and asking employees to bring in their own mugs and wash them. She explained to me how much cheaper it was to supply dish soap in each break room than the ~$1M (IIRC) they spent on styrofoam cups each year, and how they could advertise it as "green" to employees. This example is not uncommon.
These are two problems I expect as well, although I think it will probably be only 1-2 times per year. I often get into my hotel the night before a meeting and get up and go the next day. No way I'll think to check the soap dispenser in each room. So a 30 min delay in the morning likely means I'm not showering, because I won't be late to my client's meeting. That bar of soap never lets me down, and I feel cleaner than with the liquid soap.
