People apply to different programs in recessions-after being laid off at my dot com in late 2001, I went to law school.
I haven't tracked it, but I'm guessing the application volume for graduate programs overall increases during the initial stage of recessions and then tapers off-I'm not sure that application volume for all business schools would necessarily go up just because of an economic recession. My guess is that it might be up for certain schools and programs. Recent graduates who would have made an attempt at the workforce either take the K-JD/MD/Ph.d track, or people who have been personally impacted by the recession go back for an MBA etc. etc.
I actually thought about the MBA back in the last recession, but the reason I chose to go to law school at that time was that I was really young and didn't think 2 years of WE qualified me for a decent MBA program.