The use of "but" at the end of a sentence is definitely anastrophic, and does mean "however" or "as well", depending on the context. It underwent a little craze here a few years ago..
In Swiss German we have similar epidemics that befall our everyday language from time to time. Some twenty years ago, every second statement used to be topped with a final questioning "oder?". Neither deputies nor sportspeople were immune against this virus. Now there is the fashion of "natürlich", which is inserted in the most unlikely places, and it sounds quite natural, too.