Yep, they're surely not at all scrupulous but I use them all the time now, and indeed I try to buy from specific sites if possible. Amazon is the devil and they've had enough of my money.
I'm mean, to be honest, yes. I haven't purchased anything from Amazon in years. It was an adjustment, but easier than you think. Most times, I just wait a little longer for free delivery of something I don't care about getting in two days anyway. One of the other changes I made was getting a membership to a Costco type place that has local delivery for my household stuff like cereal and toilet paper. You should give it a shot.
There are a few specialized programs ebay runs (card vault, authenticity guarantee, international shipping dispatch) where they do have direct employees - not very many I'll grant you. From everything I've been able to find out, they're treated at-or-better-than the average for warehouse gigs, and the skilled staff are treated like cattle (but cattle where the rancer knows the beef tastes better if the cows are happy and have those cute brush things)
yeah definitely not. When you sell on eBay you're entirely responsible for how your item gets to the buyer (I've done it). The closest you'll get is paying eBay for a shipping label.