If I was forced to have an unreasonable fear of a semi-common object

It would be a morbid fear of bendy straws.

It's something that I'd probably encounter only a few times a year, so it's not like my life would become a nightmare, but every so often I'd encounter one and just freak out, perhaps screaming, "Get it away from me!" while backpedaling and tripping over things.

Bendy straws are also unnatural enough--straws are rigid, dammit!--and look just enough like a natural killer (snake about to strike, bird of prey ready to spear; notice the box's Darwinian stages of bendy straw evolution from gentle herbivore to nature's perfect killer) that a psychologist could have a nice early handle to work with. Yet they're also innocent enough, a child's implement, that it would also be completely befuddling and amusing to others.