Want people to use refillable bottles?
Give them a bottle.
The simple solution in this picture (plus a dishwasher to clean the used bottles) makes it impossible to not think about the benefits of refillable bottles.
Don’t scold, demand, or pressure people into changing. Show them how instead — and make it easier.
(I strongly recommend reading Switch by Chip and Dan Heath if you want to learn more about how to do this.)