The coffee shops and all she other shops, fast-foods, restaurants etc., who sell sodas, drinking water, hot chocolate etc to have a procedure to sell , for a cheaper price, their drinks, the customer in that way filling his own (stainless steel, glass etc) jug.
I said a procedure because is not complicated just to pour the coffee in the customers jug, as is complicated to change their stock movement, inventory etc. who is based sometimes on the empty cup counting .
For sure if a fast-food chain, for example, will start with advertising like " green planet coffee" (or who knows what else name) offering their product for half the price ( for example ) , the other similar companies will do the same.
I saw plenty of customers who right-away they pour the plastic coffee pot in their jug, or the PET water, or the sodas, and after that they just throw in the garbage the empty ( future) plastic waste!
Most of the bottled drinking water , actually, is obtain from the public source (tap water) and is filtered ( reverse osmosis, UV-LED, active carbon etc), some stores sell directly from their on-site filters.
Starting with the day of selling the plastic bags, more and more people came with their own bag, and now will be the same with the plastic cups!