buy Amazon erotica privately?

I don’t know if this is the right forum to ask this, but there doesn’t seem to be one.

I’ve recently gotten into a few authors who write erotica in a specific niche. I’ve bought all the stuff they have
on Smashwords, but it looks like all their new stuff is on Amazon. Is there an effective way to buy kindle ebooks semi-privately? For whatever reason, I’m OK giving Smashwords my info but am leery about Amazon. What do people here do? Is a new account specifically for erotica a thing people do, or do they just use the same account they use to buy their vitamins?