It gets worse - if you make an unrelated insurance claim while owning an undisclosed trampoline then insurance company can deny your claim due to having the trampoline even if the claim has nothing to do with the trampoline.

Not sure how common that is, but it's definitely a possibility. My cousin is an insurance adjuster and he said he denies claims for misrepresentation all the time.

So all you trampoline owners I hope you're renters or have disclosed your trampoline to your homeowners insurance.