Instead of throwing out empties, refilling and reusing them would reduce our plastic waste exponentially. There isn't a single plastic-free refill available for any products in most supermarkets or drugstores, though they'd be an easy & convenient way for everyone to reduce single-use plastic waste.
You may be interested in these active petitions
The single-use plastics that we buy our shampoo, conditioner, shower gel, body lotion, cleansers, and moisturisers (etc) in have the durability to last about 200 years. It simply does not make sense for us to use them for a few weeks/months and then throw them away, when we could reuse and recycle them from within our homes before getting rid of them.
https://www.telegraph.co.uk/news/2018/01/10/stark-truth-long-plastic-footprint-will-last-planet/
"Hugh and Anita's War on Plastic"on BBC iPlayer