I am pretty sure Jaegermeister is more popular in the US than Germany
The American pracice of drinking Jaegermeister to excess I get the impression is done because it tastes so bad, like it's fun because it's so gross and we're sharing this exceptional though still mild form of suffering while getting wasted. Misery loves company as they say.
Social drinking to excess in general has always struck me as a form of shared suffering, Jaeger is just on the extreme end of emphasizing it. Very few alcoholic beverages actually taste genuinely good IMHO, unless it's a cocktail full of flavored syrup like a liquid Jolly Rancher.
[0] https://en.wikipedia.org/wiki/Ap%C3%A9ritif_and_digestif
I don't like the taste of alcohol, but clearly some people do, so I'm thinking it's either an acquired taste (or psychological dependency) or some people just have different taste buds or something. I think it's recently become a bit more acceptable to admit that you only drink to be social, though.