That probably is a large part of their plan, and sadly it is working better for them than some of would like. BMC can't buy up every popular, quality craft brewery in the country, even if they had the cash reserves to do so, it would take very little time after no crafts were left for a whole new crop to spring up, for them it would be like cutting off Medusa's head. What they can have some level of success at is, though controlling the distribution and retail chains, limit how much Medusa's children can grow.
If I, at some point actually do make it to the place where I'm brewing for profit instead of for giggles, I would sell out in a hot second for something North of 7 figures. Yes, selling to BMC would leave a really nasty taste in my mouth, but a bazillion dollars will buy lots of mouthwash. Furthermore, why should any businessperson be expected to make their business decisions on a higher plane of principle than their customers do? American consumers have a tendency to be very principled, until being so starts to interfere with their consumption.