Unfortunately I don't see it working. Imagine having to take loads of containers to the shop. Shopping is meant to be hassle free and people are just too lazy. 15 percent is too little and needs to be more like 25 -30 percent to get people to take notice. It is like the shopping bag. Very few bring their own bags to the shop and most people buy a plastic bag at the till.
That is disappointing. People should think long term and should be motivated not only by the price but by what they gain long term with giving up using plastic bags.