I was using mail companies as an example :) MailChimp and CampaignMonitor do show their prices (Mailchimp I ended up buying from) however several other companies that were suggested to me either flatly did not show prices or had them very well hidden (i.e. icontact).
The general sentiment is correct (although I'd love to know if it's good business for consultants) but I'm not sure his example is good. The two leading mail handlers I know of are CampaignMonitor.com and MailChimp.com and both of them are pretty open about their costs.