Well, free advertising, for one thing.
More seriously, there's a long and proud tradition of....well, there's not really a good word for it. Mock-scientific publications? Pseudo-scientific would be good if the word was available. Anyway, it's stuff that fits all the forms of scientific investigation, but is completely and utterly fake.
Here is a personal favorite. Plastic clips for bread bags aren't biology, yet someone spent a rather remarkable amount of time and effort pretending they are. I also own three different works on classification of dragons. The geology of Skyrim discussion is remarkably interesting; the game accidently makes perfect geological sense, even the underground portions.
Here's the thing: scientists are nerds. We spend a lot of time working on obscure and arcane concepts, and we actually enjoy using them in weird ways. It's a way to both practice our skills in novel environments, and to have a bit of fun with our jobs.
That said, we are supposed to warn people they're seeing something fake. It's all fun and games until someone believes it; then it becomes fraud. Obviously within reasonable limits, that is--no one expects scientists to remove all possibility of crazy people believing them, because crazy people are inherently unpredictable.
That's the thing that always gets me about cryptid research: the stuff they're looking at is astonishingly dull. A bipedal ape is only interesting because we are bipedal apes.
A plesiosaur is interesting, but it's also the most popular dinosaur out there. In contrast, I can show you stuff that's so weird that you couldn't make it up in fiction--no one would believe it. Bipedal crocodiles that ate dinosaurs. Giant carnivorous turkeys with stubby back legs and claws the size of sabers (we think they were carnivorous anyway; we're not sure). Barnicals that exhibit a life history remarkably similar to plants' alternation of generations, and which
take over the minds of their hosts. Then there's the REALLY weird stuff, by which I mean stuff that's so far out there that we have no idea how they even worked. Archaeocyathids are a great example. We kinda sorta think we know why they're shaped the way they are, but that's as far as it goes. Vendian stuff is so weird that we've been debating what they are for
over a century. We aren't sure if they're animals; most people are convinced, but good arguments against it have been made. And those are just off the top of my head; give me some time and I could come up with many, many more. Even the normal stuff in paleontology is weird and wonderful. I once found the lower third of a Camelid scapula--and that piece was as big as my whole scapula. This thing could look in a two-story window.
My point is, cryptids, even if they were found to be true, would be pretty tame.