Sounds like the good old bait and switch....
Which is ILLEGAL in Canada.
The OP and others in this thread may want to take a read of this and consider filing a formal complaint with the Better Business Bureau:
http://www.competitionbureau.gc.ca/eic/site/cb-bc.nsf/eng/00522.html#sale
One of the defenses available to the retailer in this situation hedges upon a "rain-check" being offered as a show of good faith.
In this case Marstar obviously had the ability to offer a raincheck, however they made the conscious decision to try to sell the same exact product that was advertised (and already technically sold) less than a day before at 3X the price.
The other defense rests on non availability of the product.... (Again Marstar does not have a defense...stock was readily available on Marstar's own admission)
Not just illegal but also a PR nightmare....