I have only come across this term on MN but i think I wintessed it first hand... whats it all about?
Family in lemur enclosure at zoo talking to keeper.
Keeper "you can get a little closer if you want"
Woman "we don't need too thanks we honey mooned in Madagascar so we have seen so many lemurs up close"
Keeper "oh okay, bet that was great"
Woman "it was amaaaazing... we could hear them all around our cabin at night aaaaahahahahhaha" (not sure why this was funny- but apparently it was hilarious)
Don't get me wrong I wasn't jealous in the slightest... nothing i would be creeped out by more than animals at night...
It just felt like one up man ship at its finest. I mean why go in there if you only want to belittle the experience 
Whats the worst humble brag you have witnessed?