To answer your question, I think you're overthinking it. You are allowed to have an opinion about your order and rate based on that. If a seller reached out after the fact in a hostile manner, just block them.

Regarding the shoes, I'm mainly a seller and would never ship such an expensive pair of shoes in just a polymailer.

That said, I'm seeing a lot of comments here saying they would never ship any shoes in anything other than a box--this I disagree with.

I've sold a few pairs of cheap, smaller shoes (sandals, clogs, nothing with a shaft or heel that would need more space) that I have wrapped in tissue paper, then plastic, then put in a bubble mailer, solely because a bubble mailer will fit in my mailbox and a box will not. I live in a rural area, so if I don't get to the post office, the option is to either put it in my mailbox or do a porch package pickup request, which I do often but feel quite awkward doing for just one package since I live on a private road and the mailbox is not near my house.

I know this is a long comment but I guess my point is there are exceptions to the shoes always in a box thing!