To just fill you in, Coffee growers grow coffee because the cost of growing coffee is less than the local wholesale price (most of the time.) It is possible to subsist on the profits of growing coffee(depending on where you are).
The price per TB being charged to the consumer is $48 a year. which is significantly less than the initial setup cost to become a data host. (pi + sd card + hdd) That's before we get to the opex of paying for an ISP, (and any bandwidth overages) plus power and general maintenance.
Thats assuming that the company is selling at the price it pays the "hosts". I'm assuming they have some ambition for profitability.
which leads me back to the original statement: you're reliant on a bunch of randomers Who didn't really think about the economics subsidising this company.