Imho the current implementation can be considered flawed, since one may want to print the photos that make the seed, for example, for remembering easier.
A brain wallet (also not recommended) could work from photos and other objects too: on the wall in my living room from left to right I see: Heater Speaker Bob Alice TV Speaker Fireplace Wedding Lamborghini Piggybank Drawer Litterbox and Curtain. Enter it into Bitaddress: 1pZNXZ6PUfpHjmgcQhcYkEVJnMStJfj7C!
As long as you don't change your living room, you can probably recover these funds. But it's not the most secure storage system.