Guess you never understood Jainism.
You didn't understand the reasons and principles behind it.
Don't spread wrong based on half knowledge about something.

Yes, Jainism believes in non violence but it doesn't teach you if some attacks you don't fight back.

Jains believe in god.

Fasting is your choice, no one's forcing you. It's not compulsory. It's just a way through which we can get toxic substances out of our body. It makes us healthy.

Milk is an animal product but it's not non vegetarian like egg. So that's why milk is alright to consume not egg. Do you want to eat someone's baby?

Potato, Onion are to be avoided because they have 1 - organ creatures which you can not see under naked eye. In order to save them Jains avoid eating them.

The mantra you're talking about, it means gratitude and respect towards god and saints. It has powerful elements which if you pronounce can produce vibrations in your body and can help you fill with positive energy.

Being free from materialism is for saint. If a Saint keeps something, he's nothing. He's not saint. For a person living at home or a follower he is free to accumulate as much wealth as he wants as long as he doesn't have pride.

Jainism teaches us to conquer our mind and body.
Learn from right guru for right knowledge.

Try to know scientific reasons behind it.
Everything has a scientific reason behind in Jainism.