This was the situation in 2010 when the Sky broadband packages were renamed:
Quote Originally Posted by http://www.broadbandproviders.org.uk/isp/sky
Pricing for these broadband packages on their own without Sky Talk run five pounds per month for the Base plan, ten pounds per month for the Everyday plan, and fifteen pounds per month for the Unlimited plan.
If my memory serves me correctly there was a hue and cry about free broadband now costing £5. Sky's response to this was that customers could continue to receive free broadband if they took out a Sky calls package. At the time there was no requirement to have Sky line rental.