Not very wise to export your (assumed) copyright-infringing activity over to a third party that has complete records of who you are. Folks have been sued for less.
However, they're still operating, they only know my e-mail, nothing else, and they honor DMCA take down notices.
Oh, and the company is local to me.
They don't access to your card details. Just an API integration, that's all.
So, yes, people easily could be sued for torrenting and plenty of people have suffered significant penalty.
[1] https://en.wikipedia.org/wiki/Legal_issues_with_BitTorrent
FWIW almost all the people listed on your wiki page were tracker operators, but I am aware that there have been a few exceptions.