Fad words enter and exit the language quickly but are never recognized. There are rules on how philias and phobias work and they are generally based on Greek, not Latin, roots.
English is infinitely malleable and whether you (or I) like it or not, changes come about (and stay) that refuse to follow "the rules".
The blended Latin and Greek word "umbraphile" is just one such example. It also isn't a "fad" word. It has been in use since the early 90's and has steadily gained greater use and wider acceptance as time has passed. Hardly the hallmark of a "fad" word.
Face it, Tom, you're screaming in the wind at this one. You've lost. And frankly, I'm okay with this evil little word that refuses to follow the rules. You may not be, and that's okay. There are other words or new uses of words that drive me batty, but there they are. The absolutely travesty that has befallen the word "literally" in current usage is an example. I loathe people who use it incorrectly, but there isn't much one can do about it besides silently curse them and their misbegotten progeny forever more.
For revenge on Mookie for forcing you to engage over "umbraphile", I suggest ordering an extra large Hawaiian pizza and sending him a picture or two to enjoy. He'll be gnashing his teeth in spiritual agony over it claiming to be "real" pizza. He'll be standing in front of the oven, shaking his fists, shouting "get off my peel"!
Real words. Real pizza. Y'all gotta get over it.
Toodles!
-Samantha Jones, SatC