In retail, shelf space is costly.  Businesses tend to stock what people are buying.  I don't know if carriers are giving up on BlackBerry as much as consumers are.  People just aren't buying them...or at least not enough to justify the space they take up on a shelf.  I know it may make some angry but its true when you think about it.  Who wouldn't want to stock a product that isn't selling and generating profit? 

I work in the automotive industry...and I can tell you that we don't stock what people aren't buying.  One of the lines in our network is Buick.  While an amazing product to some...we usually only take the required amount of a specific Buick model to adhere to our franchise agreement with the manufacturer.  It's not that we don't want to sell Buick's...it's just that we don't have a demand for them in our current market...therefore we don't stock any more than we have to take per our agreement with General Motors.  If folks suddenly started buying them and there was a major uptick for the product...we'd stock as many as we could sell.  But when a product like Buick (in my segment of the market), and in this scenario, BlackBerry, doesn't justify its existence (i.e. sales) then they get the boot!  It's nothing personal and I don't believe anyone is out to ruffle the feathers of a particular customer...that just the way it works in retails...in my opinion...