It is entirely up to the Faerie with what sortof psychic resonances it feels the most comfortable with. The Feywild reflects the psionic conscience of the material world, so it is as wide and varied as the material world is. Depending on the different environments on the Feywilds, the Fey Creatures that live in the area take on some similar characteristics to "evolve" in that environment. This makes sense for some Summer Fey & Summer Pixies to be passionate, spritely, fast in many cases. Quicklings would take the heat of haste from around & grew into that magic.
So for something's creature type to be fey - to be fey, means to have a connection to nature and that connection to nature means that a fey would feed off & flourish from the emotional energies; not just through currency. It would be similar to walking into a sauna. You feel the heat, but it's not like you get burned alive. The fey can sense the emotions, and pull & push on it. They don't drown in it unless it is unnaturally made dense.
Material plane creatures cannot sense emotions. With training they might get some sortof sense, ones more empathic; ones with a high enough insight to gauge a creature's disposition but they have to practice at it, train to do so - whereas Fey it comes naturally as if reading a picture book. Slightly difficult to describe, but for the Fey that are able to sit still long enough to do so... it could be understood. This is where many of the annoying misunderstandings come into play. For the elementals & the Fey deal with nature. That's because people keep shortening it unrealistically. The Elementals deal with the nature of the physical world, the Fey deal with the nature of creatures.
Fey are known to enslave creatures, especially mortals - through various forms including taking their names so they can't go back. Their queen, especially, abducts men to be her consorts or playthings.