I don't think hackers can get seeds from your wallet. except that happens when you accidentally download and install an application from an unknown party and you permit it to access your device.
I don't know how people might store their seeds. some just write the manual on paper and keep it in a locker. but I'm sure some save it offline or online on their devices.
when hackers don't get access to your seed, they won't be able to access your wallet.