Ask the sellers why it's so expensive.

i actually found it at half price books the other day for 10 dollars. TOTALLY jumped on it, after all these years of searching. 
have you tried going to a flea market?

$35 is a good price methinks

It was late on in that generation so likely not that many copies are out there.  Not like super rare but enough to push the price up slightly.

Because it's awesome!

Because it has a poo monster in it.... A FUCKING POO MONSTER!

That games easily worth full price.
Not half as bad as the time I saw Super mario RPG for 500 dollars in a game store.

" That games easily worth full price. Not half as bad as the time I saw Super mario RPG for 500 dollars in a game store. "

Yeah, the original Conker's Bad Fur Day for the N64 is on my list of old games to look for and purchase. 
 
I laugh every time I sit down and play Diddy Kong Racing and Conker is just a cute little innocent squirrel in that game. (But I wonder whatever happened to Timber the Tiger and Pipsy the Mouse. TipTup the Turtle at least got himself into a couple of games)

It's expensive because you want it.

because it's rare

Supply and demand. Supply is low. Your demand is high. Thus, price goes up.

"

because it's rare

"

Just be glad you don't need the PAL version, I just paid $105 for only the cartridge...

Yeah, the original Conker's Bad Fur Day for the N64 is on my list of old games to look for and purchase.  I laugh every time I sit down and play Diddy Kong Racing and Conker is just a cute little innocent squirrel in that game. (But I wonder whatever happened to Timber the Tiger and Pipsy the Mouse. TipTup the Turtle at least got himself into a couple of games)

Michael Pachter.