Well, people on the Net are not in the habit of paying for information they feel they can get for free. There are other problems. People don't like getting 'nickel and dimed' to death. The fear stems from a feeling that a constant trickle of microtransactions of cybercash will add up to a deep drain on the account. The anonymous nature of the transactions is also problematic.
Anonymity cuts both ways.
It stands to reason that without a paper trail, risks rise sharply. Instead, these providers often make the information available at no charge and attempt to have their costs covered by advertising. At the present state of the Net, the high volume advertising dollars flow mostly to the massively active sites - mainly the search engines like Yahoo , Excite and others. The most active homepages on the Web is the Netscape website. They enjoy a large revenue stream from advertising.