I think I can see the argument that this legislation would harm craft breweries. I think it was in the movie American Beer that some head brewers at the bigger craft breweries indicated they distributed either through BMC or their subsidiaries. So, if regional corporate buyers are going to be controlling what makes it on convenience and grocery store shelves, they're likely to buy more product distributed through BMC and their subsidiaries than from smaller, craft breweries with independent distribution. This would be the case because the BMC-distributed product would probably be cheaper (because the sales volume would be higher) and there would probably be at least some pressure from those distributors to keep pushing the big boys' product (BMC is BIG account -- Mr. Corporate Buyer would not let that relationship dry up by catering to small-time brewers).
On the other hand, I don't live in CO so I don't know the ins and outs of regional distributor/retailer relationships. I do know, from my limited experience traveling in CO, that there is a huge craft brew scene. I imagine this scene has at least some influence on consumer culture and, ultimately, consumers are what drive sales. If consumers want the smaller breweries' product to be on the shelves of their local convenience and grocery stores, then in the the immortal words of Jean-Luc Picard, I'm sure they could "make it so."