I always believed that they were one and the same. Mr. Clubtail seems like he was meant to be random extra in one movie who later became convenient to reuse in later movies and eventually became a character in his own right. I did like his presence in other movies, it gives the valley some local color. I’ve mentally kind of consolidated his many slight varying depictions to him being gruff but affable. He is generally a descent sort, as seen in his cordial exchanges with the gang like in movie 5 and him accompanying the rescue of the kids in movie 3 (I kind of headcanon he went on the behalf of Nod’s family, who presumably took another evacuation route for the fire and so weren’t present to help rescue their son).
But he can be impatient and rough in manner, as seen in movie 12 when he expresses annoyance at the Great Day of the Flier shenanigans and him bopping Guido on the head. He isn’t above falling for the usual valley hysteria as seen with the Tinysauruses. In “The Amazing Threehorn Girl” TV episode, he was among the crowd who excoriated Cera for lying and even suggested she not be allowed to stay in the valley. Good people can do very questionable things, so I don’t see his behavior with the sweet bubbles as that far off course.
I’m kind of under the impression his sweet bubble eating sessions are something he prefers to keep quiet if not a secret so he could enjoy them on his own. He isn’t in the mood to share in these times. Some people can be quite territorial over their favorite food (Which I’ve been admittedly at times), and I can see how eating lots of that favored food can loosen your inhibitions toward others whether those sweet bubbles are fermented or not.

So he doesn’t show much hesitation toward being rude to the gang and even spraying them with juice. I think this rudeness is both sincere and played up to make them go away so he can eat in peace. Though some of his old friendliness is still present, as when Ducky sincerely tells him about getting sweet bubbles for Ruby’s Star Day, he immediately offers to share, eager to share happiness with someone who also likes Star Days and sweet bubbles. I wonder if he and Ruby ever do some activities and bonding over those things. It might be cute.
I can understand why his appearance in the Star Day episode might be jarring. His voice was different from the other ones he had so far. His VA for that episode is the same as the one for Redclaw and Screech (And Saro). This amuses me. Plot twist: Redclaw was Mr. Clubtail all along!