There are a couple of things that could be going on there. First, you never put them in the fridge, so they never hardened up in the first place. Second, different fats have different temperatures at which they congeal. I keep olive oil in the cupboard, and it stays liquid, but if I stick it in the fridge, it will solidify. And fats have very odd melting/solidifying profiles; they do not melt at the same temperature they harden.
Indeed.
“And fats have very odd melting/solidifying profiles; they do not melt at the same temperature they harden.”
Did you have pchem in college?