I bought a weed whacker directly from the maker about 5 years ago, and since then have received literal tons of their catalogues in my tiny mailbox. They send > 80% of all the mail I receive. I've regretted it ever since. Now I feel like I need to keep my address a secret unless there's a good reason not to. Amazon has had it since the last century and has never abused it.

I'd buy more from such if it was easy to hide my personal info from them.

This. Amazon has the best checkout and delivery system in the world, and that alone is worth a few extra dollars. The excess crap gets caught in the appropriate filters and I just end up with my item in a box.