Ooma internet phone -- What are "standard taxes and fees"?

They are advertising this as a product for free internet phone service, except for “applicable taxes and fees”. That’s what their website says that too, but never explains it. There is a rate chart for international calling, which wouldn’t be a part of taxes and fees.

I use Google phone for some domestic calling , and there aren’t any charges (to me) for that. I understand Google will start charging a fee next year – is there a chance they are paying something on my behalf right now? Are there any Dopers out there in other states or countries who are being taxed on internet calls like Skype?

Here is their taxes & fees calculator.

This post includes a quick chart of their taxes and fees.

That $3.47 per month in the chart is actually the exact number I pay in my area.