Already back in 2008-2009 a study was conducted in Great Britain which showed that the lightest possible wine bottle suitable and durable enough for storing and transporting wine could be as light as 300 grams. As a result of that research project wine bottles of that weight class have been used there since year 2010. It is a considerable achievement, because tradition has a powerful role in wine production and there are big cultural and country-specific differences in the weights of bottles.
How about other product categories where glass bottles are used? Some spirits producers have long been actively developing their packaging: from their own starting points they have reduced the weight of the glass they use; maybe most typically foreseeing available long term cost savings. As a customer you do not notice a difference in the quality of the end product. Also PET bottles are used in packaging from the producers’ own initiative, even if originally for other than environmental reasons.