AFAIK there is nothing illegal about charging HST as long as they rebate it. Obviously they haven't done that. And of course it looks especially stupid for a company that has been doing business in Canada for quite a few years.
I doubt Revenue Canada would get too excited, but if they do not refund the 64 cents I would file a complaint, just because of the annoyance it is causing you.
If it is annoying enough write a short letter/email to your local MP and the opposition member for your riding.
If you love your Kobo Glo, just buy your books elsewhere and or get library books. Living well is the best revenge
Helen