Toll-free numbers should not require a calling plan
For all phone companies I'm aware of, including ILECs, when you get a toll free number, the number is free and you only pay for the minutes.
For toll-free numbers on Teams, I'm required to buy a calling plan as well. That's effectively like getting taxed on tax, or paying your minute rates twice.
It was a good move to remove phone plan and E1 license requirement (I found a way around by using Skype plan 2 instead). It'll make Teams more useful to a lot of people for voip calling, but for good adoption for toll-free, you need to remove this last hurdle. The only reason my client's sort of willing to pay it is because they're a die-hard Microsoft fan.