At this point, non-dairy milk alternatives are par for the course at many coffee shops.And oat milk has popped up in recent years as a flavorful and froth-friendly option for baristas.This week, Starbucks announced it will finally offer oat milk at stores nationwide beginning next year.The news was released as part of an update on the company's sustainability efforts.Starbucks is also making a $50 million investment in a program to help coffee farmers grow more sustainably.But currently, those looking to reduce their dairy still face an extra cost at Starbucks stores.However, that non-dairy surcharge may be on the outs altogether.We expect costs [of non-dairy milk] to come down as the supply chain for plant-based options matures and we will pass this onto our customers, Starbucks