We’re proud to say that we fill only Funky Buddha Brewery growlers for two reasons. 

First, sanitation and cleanliness is important to us, especially with a glass bottle we’re going to put our beer in. Many people trade our growlers across the country, and an unsanitized growler that’s being shipped in the mail while not refrigerated is a recipe for spoilage. So, instead of cleaning and sanitizing growlers to order, we choose to swap your growler with an already cleaned and sanitized one when you come in. By doing this, we can ensure the quality of our beer in growlers will remain consistent. We think it’s worth the effort, and we hope our customers do to.
Second, our growler machine is calibrated to fill our glass, which is a certain height and size. Other size or shape bottles have not worked well on our filler in the past, and we really try to use this machine whenever possible since it provides an oxygen free fill of the best quality. 
We understand most people have a plethora of growlers so buying more is not always a great option. We are talking about how best to fill non-Funky Buddha growlers such as stainless steel and insulated ones that do preserve carbonation and temperature longer. Thank you for your understanding!