Has anyone encountered an issue like this one?

I live in the USA, I have an Aeroplan cr card issued by Bank of America in USD.

I purchased AC tickets with Aeroplan card on aircanada.com, Bank of America charged me 3% fee on the total purchase amount because the charge came from Manitoba (outside of the USA). Called BofA and they will not take off the fee.

Is there anything I can do to avoid this fee in the future? Can I force the website to charge me from the US?