"A Screech-In sounds like something a frustrated ornithologist might indulge in, or a Beltway ritual for stressed-out drivers. But in Newfoundland, it's a traditional ceremony to induct CFAs ("come-from-aways," Newfese for tourists) into the Royal Order of Screechers and thus make them honorary Newfies." --Paula Stone, "A Trip Off the Old Rock," Washington Post, Sunday, April 22, 2007; Page P01.
Actually, in all seriousness, does "being immensely popular with visitors" commonly imply that something is traditional? Not sure why "despite" should have anything to do with it.
I'm sure it's just a fun, welcoming way of drinking oneself completely silly. (If kissing a cod can be said to be silly. Frankly, I do it all the time. Well... if there were more than about eight cod left in the Atlantic Ocean, I might.)
An induction ceremony by which come-from-aways may be initiated as Newfoundlanders. Generally involves a shot of screech, a declaration of faith in New Foundland dialect and kissing a cod. The ceremony, despite being immensely popular with visitors, is in fact an innovation that dates to the 1970's at earliest.