It seems that certain payphone operators in the USA no longer allow the use of Canadian calling cards to make toll free calls back to Canada. I made two calls from the State of Washington last year that cost over $40. The calls were added to my regular phone bill even though we pay for a block of long distance. We rejected the paying the calls and Clear View Communications put the amount into collection. It seems that the consumer is caught in the middle between providers who can't reach reciprocal agreements with one another.
There are two companies at fault in our case. Clear View should not have allowed our call to Bell's 'Welcome to Canada' service to proceed without some warning that extra charges would apply. Bell is at fault for failing to notify its customers who use the Calling Card service from the US that in some states (California, Washington, Michigan, Colorado, Florida, and Iowa) their calling cards may not work and extra charges will apply.
In the end, Bell credited our account an amount equal to the extra charges, but not without several phone calls to all parties.