These Griffons have quite a history with those bar fights of theirs, way back when they were young adults. It has become something of a tradition between the nine Griffon elders over the years but the frequency of the particular occurance has lessened as the Griffons have grown up. In some bar places, they're known as "The Truculent Ennead", "Bar Breakers", "Tavern Terrorisers", and "Saloon Scufflers". There, the bar workers make sure the tables between the two groups have a good distance from each other and that they're guarded, in case they'll have to break the Griffons up during a fight; still, most of the time, they don't have to as, usually, the elders behave with civilisation or only one of the groups is present.
Those arguments are mostly caused by Grandpa Garvey, Grandpa Gillan, and Grandpa Gino's sarcastic remarks that often lead to a slight strike. A small punch turns into a small swift kick; the swift kick is returned with a firm slap across the face; the slap is returned with another slap, and the slapping goes on and on for a few seconds until things get out of control. They arm-twist each other, crash one another on nearby tables, they usually bust various objects on each other's heads, and so on. Grandpa Gruff lost three fangs once. However, the Griffons among the two groups often tend to get a little carried away during the fighting and end up accidentally and unintentionally hurting some of their allies — as displayed in the image; Grandpa Gruff accidentally hits Grandpa Gyeong with a grape juice bottle and Grandpa Gareth unintentionally crashes Grandpa Gideon —, as well as becoming rather oblivious to what's happening around them. When that happens, the rest of the bar patrons and workers quickly rush for cover from the imminent fight, although there are some who cheer and watch while eating popcorn.
Sure, there are cool fights here and there, but they all know it's not always worth it. With all the brawls they've had over the years, the two groups have lost count of how many times they've been kicked out of/ temporarily banned from bars and taverns around Equestria. The elders don't really see it as fighting though. Most of the time, they seem to enjoy it and often consider it as a way to exercise. When the fighting stops and there's nothing left to use as ammunition or they're tired, they all somehow end up sharing some cider and a good laugh about how they tend to act like cubs even though they're full grown adults.
After every fight, they just need to come up with a good excuse to explain those injuries and the repair bill to their wives and grandchildren/ grandnephews.