There are many alternative options to store those phrases online, without anyone even noticing it.
You just need to camouflage it a bit with clever techniques that will conceal it's real purpose. (Using templates and splitting it into many pieces that only you will be able to decipher)
Of course it's possible. But if enough people do this, I bet some of them lose their money, while others are unable to recover their seed on their own. And that's why it's generally not a good idea to create your own system.
Some people stay in areas where natural disasters are more prevalent, so you cannot store this in one geographical location.
Even a safe deposit box in a bank far from your home would be a better idea. Or 3 safe deposit boxes, each storing 16 out of 24 words.