Carbon steel deforms over heat. Also leaks oil through the pores. Or maybe I should have bought a more expensive pancake pan? Otherwise I like it; using both but I am extra careful with the cast iron.
What do you mean it leaks oil? I’ve never noticed any like that.
https://www.amazon.com/Kitchencraft-Non-stick-Crepe-Master-C...
(the reviewers that claim it sticks have not heated it up properly and the peeled off "teflon" is just burned crêpe)
In your case I think that oil gets over the lip and around the pan.