All due respect, I guess it depends on whether you think the inconvenience of spending a bit longer on the - to be fair, boring - process of checking out is worth the 15% fees bandcamp would be taking from the artist on any other day.
Also, why has your bank not cottoned on that you buy music on bandcamp? Surely that would be an easier fix, especially for an institution with so much money. I had my card blocked twice, no problems for at least half a year now tho