to think those paper/foil 'lids' should be discarded?

[postmanpatscat]

I don't get why some people keep the papery bit on top of the marg/spread after they have opened it. Surely it just goes in the bin as the plastic lid does a sufficient job on its own?

YANBU, it's just a pain in the arse and you always get butter on your finger after it flops back down after you peel it back.

YANBU but it's blatantly Women's Work and only myself, in our household, can attend to it

YANBU

I told my DH that if he leaves it there one more time, he'll find it stuck to his side of the bed.

Use butter instead.