Why do I need to give my credit card info to sign up for a new Yahoo mail account?

I just tried to sign up for a second Yahoo email account, and after I went through the usual sign-up process, another screen came up saying I needed to provide valid credit card info and proof that I’m 18.
I’m definitely not comfortable providing that info to get a Yahoo account.
What’s going on?

Dopo la bolla dei mutui subprime, scoppierà quella delle carte di credito?

http://it.biz.yahoo.com/20102008/57/l-america-paura-puo-esplodere-bolla-credit-card.html

How do I change my Credit Card NUMBER for premium services?

I have 2 Yahoo HOSTING accounts …2 domains, 2 websites
I changed one, but cannot delete 2nd hosted account.
Never a problem with existing bank’s credit card which covered BOTH
hosting accounts, until now when I needed to REPLACE credit card number due to vendor billings which needed to be cancelled and bank
advised only way was to be [...]

Yahoo credit card comparison?

Okay, so it’s been a year (about, maybe more) since I accessed the feature…..but I remember being able to compare credit cards. You entered in what your current card is/was and what you paid (annual fee, as well as monthly balance) and….maybe one or two other details, and Yahoo pointed you to cards that [...]

What is the cause of all the credit card offers to me?

OK, I paid my rent on time for the last 4 years with 2 late payments in the first year.
I paid my power & light bill on time for the last 2 1/2 years, after the first year with out a late payment the sent me back my deposet for $150.
1 year with [...]

How do I find a credit card account that will allow me to accept mail order payments for a small business?

I am working with the publisher of a small journal. We need to make arrangements to accept credit card payments for subscriptions and advertisements.
How do I do this? What are the search terms I’d put into Yahoo or Google? (If I just enter “open credit card account”, most of the [...]

How to buy a pre-paid card for yahoo phone out? Or How to purchase a card through any bank credit card?

For example, I have a credit card from Bank “X”. Please let me know how to buy a pre-paid card for yahoo phone out through this credit card?

Why do you require visa card info to sign a child up for yahoo to participate on message boards?

I just tried to sign my child up with a Yahoo ID to participate on the math message boards, but it would not let me continue without visa card information. Why do you need that information? I thought this was a free service.

Any advise on buying computers from foreign websites, credit card NOT ok?

I’ve noticed really excellent prices on computers listed in pricegrabber and yahoo comparison, but websites are foreign and FAQs state payment must be wire transfer. Any experience with such.

What do you think of Bank of America raising credit card rates even on good accounts?

http://finance.yahoo.com/banking-budgeting/article/104466/Card-Sharks