And one more thing: does it matter which email service I use (Gmail, Outlook, etc.), or could some services just block these emails from the casino, leaving me with nothing? Because I don’t want to “expose” my address and end up without the promised funds.

I understand your concerns, but it’s actually much simpler than that. I recently signed up with a few casinos from a list on a review site, and I can tell you that email verification is just a standard KYC step to confirm your identity. At MilkyWay, I activated 20 free spins with the promo code SGR20 in under a minute. The email arrived instantly. While we're on the topic, you can check out https://nodepositau.com/email-verification/. There's information on various casinos there that I think will come in handy. As for spam, you can always unsubscribe from newsletters in your profile settings. By the way, I only use Gmail for email services. The most important thing is to choose licensed casinos because they value their reputation and don't leak data.