Hi@blue48-6666, large sellers can make that business model (too-low price & free shipping) work because they're selling at a high volume. They may net only pennies on each sale, but with a high volume of sales it can become substantial. Also, with a high volume of shipments, some may have additional shipping discounts directly from the carriers.
Look at their feedback. To keep costs down, some skimp on packaging, quality, and customer service, but the resulting negatives & neutrals often don't matter to buyers looking for rock-bottom prices.
Some new sellers do sell at a loss at first because they're trying to build up experience and feedback. There are some who may not know any better and are just copying what the larger sellers do.
As a small seller, don't try to directly compete with the too-low price / free shipping / high volume sellers. Look to do everything better than they do: better photos; photos of actual items, not stock photos; better descriptions; better customer service; better packing with care to avoid shipping damage, etc. There really are buyers who look for that and are willing to pay a little more to avoid the buying problems they've experienced, because they've learned the lesson: You get what you pay for.
tree*fern
Volunteer Community Mentor