baht is an International transfer. I used to use Bangkok bank for the transfers but it was no longer classified International so I had to open a Kasikorn account for this purpose.
I can do but prefer to use my card. If I use my Chiang Mai BB card in Sukhothai I get charged and the same if I use my Sukhothai Kasikorn card in Chiang Mai I get charged. So I just transfer funds to avoid the charges. These charges have been applied with my BB card for the past 18 years and about 5 years with my Kasikorn card.