The issue here is that your contacts did not agree to you sharing their information with a third-party.

I don’t know. If you give me a soda, that soda becomes mine to do what I want. I can pour it on the ground, drink it, or give it to someone else. I feel the same way about ways to contact someone. With today’s technology, they can block people they don’t like but it’s not my job to be their gate-keeper.

The poor analogy, mild sociopathy view

Can you explain what it is that gives you the right to hand other people's personal information to another entity?

Especially as part of a commercial transaction to a for-profit company?

"Hey, Bob! I'm going to give some company your name, phone number, occupation, and whatever else I know about you stored in my contact list in exchange for a beer. Is that OK?"

Do you make someone sign a legal document when you give them your number detailing the uses and limitations of how they can share your number? No. You don't.

Once you give your info away it is not "your" info anymore. It is info about you, but you do not own it.

Is it rude? sure, but not illegal.

Lots of things are amoral but not illegal. I also don't think anybody above you claimed it was illegal.

"what gives you the right..."

okay.

> Is it rude? sure, but not illegal.

Depends on the jurisdiction. Under the GDPR this might very well be illegal, though obviously enforcement of it is significantly lacking so it's unlikely to ever actually be tested in court.