Вот например как мне ответили админы на мой вопрос (могу ли я написать мой персональныы адрес понравившемуся мэну) на том сайте где нельзя обмениваться персональными адресами:
While we appreciate your frustration, we must point out a couple of things.
First of all, we are not the only site that prevents the exchange of email
addresses: many other high-profile sites forbid members from exchanging email
addresses by on-site *******.
Unlike other sites, however, our reason for doing so is concern for our
members' security. As you may be aware, fraud is rampant throughout the
internet, and dating sites are no exception. We implemented our no-email
policy in response to complaints from members about scammers posing as people
seeking mates who were luring other members off-site by sending them their
email or instant message handles. These con artists almost never attempt to
perpetrate scams by post or by phone, as these are not anonymous means of
communication. Therefore, we determined that it was in the best interest of
our members to ask them to use the ХХХ email and chat systems for online
contact and to use telephone numbers or live meeting places for off-site
contact. We realize there are draw-backs to this, but it has been extremely
effective in scaring criminals away from our site onto other sites that offer
no such protection.
We hope that this has explained our position. We appreciate your patronage
enormously, and we take your feedback very seriously. Your satisfaction is of
the utmost concern to us, and we do our best to balance enjoyment with security.
Во как они заботятся о нашей безопасности. Просто сразу так и хочтся спросить у каждого кто вписал свой адрес в первое письмо - "а ты не скаммер случайно"?
А то, что номера телефонные раздавать сразу незнакомцам - это у них нормально

Это не опасно
