I agree with the grandparent poster that not collecting information should be the default. re: collecting IP addresses: I run my web sites behind Nginx and doe

I agree with the grandparent poster that not collecting information should be the default. re: collecting IP addresses: I run my web sites behind Nginx and does have rolling logs, but I ignore IP addresses. For your e-mail use case, I think a reasonable compromise is asking if the user is older than 13 and what alternative is there but to trust them? Personally, I think that collecting e-mail addresses for people signing up for a newsletter is a great example of when it is perfectly fine to collect private data.