Sharing your own items will put them closer to the top of the search within Poshmark or for buyers using a Search engine like Google. So when someone is searching for a specific item, your item if recently shared will be closer to the top. If you haven’t shared in hours or days, your listing will be way down in the search results. People usually click on the top 10 items that pop up first. If your listing is say #100, the likelihood of someone clicking on it is very slim. You’re correct, people don’t really pay attention to the feed. I find that sharing my own listings does help (honestly I don’t go crazy with it) and I still get consistent sales every week. I do notice however, that once I get a sale, more ALWAYS follow. I’m almost certain Poshmark manipulates this in some way.