At least Wiccans believe that what you do to others comes back to you 3-fold or 10-fold or something. And Hindus, Theodinists, and Asatruers believe in the possibility or reincarnation. What do atheists have over them?
I've talked to quite a few Wiccans and other pagans too. The first thing you should know is that Wicca is a watered down, pansy version of witchcraft. It's something for novices who live in suburbia to dabble in to make themselves feel powerful and special. Wiccans get an immature thrill out of being rebellious against the greater Biblical influence of the West.
Historical pagans committed human sacrifice all over the globe. They sacrificed people to the sun, to the moon, to prevent natural disasters, to ensure a good harvest, and for other reasons. Modern pagans continue this tradition in Africa and other remote areas of the world. If you don't believe this then look up why albinos in Africa must fear for their lives.
Modern Wiccans claim to be all about loving nature, etc. That's only what's on the surface though. If you talk to them a while the truth comes out. They acknowledge that magic can be used for good or for evil, and that in fact these are just two sides of the same coin in their belief system, and that furthermore there is no "good" or "evil" in the way we would think of it. Most will initially claim that they believe that it's wrong to hex people or cast harmful spells, but most of them will admit eventually that they don't believe that it's wrong to hex certain people they would see as harmful. They will often gladly hex "Christian fundamentalists" or other people they see as "hateful".
The Wiccan rede also has its roots in much darker modern magic tradition. The Wiccans say "An it harm none, do what you will". This is a copying of Aleister Crowley's saying "Do what you will shall be the whole of the law". Without the Bible or any other type of moral guide beyond themselves, it's up to the individual Wiccan to decide for themselves what is "harmful". They are then free to hex those they see as worthy of it even when they claim they only use "white magic" and never hex anyone. There are some who move beyond Wicca into other things like chaos magic, practical magic, and even into black magic. All of these things have the same basic roots to them and aren't necessarily fundamentally different, though the Wiccan dabbler will often claim that they would never do anything dark or scary.
I've been asked a few times not to talk about Hindus so the only thing I will say in this post is that people have died being sacrificed to Kali and there's some stories that this still happens. There are many branches of Hinduism from secular to deeply religious too and so I can't really speak about them as if they were all the same. New agers and suburban pagans do seem to have a fascination with Hinduism though and eastern religions in general due to their strong rejection of Biblical traditions, so that's something to keep in mind.
Odinists and Asatru followers are honoring the same evil deities as the Thule society did. You can't honestly think that would lead to anything good.
At least atheists won't be sacrificing you to the sun or moon or putting a hex on you.