I don't think anyone except the adcom can provide insight into how merit scholarships are awarded. I received one from Ross and can't tell you why I have one.
MBA programs that are trying to recruit students away from the top 10 (I'm using this designation very loosely) tend to be more generous with scholarships than those in the top 10. I have a few classmates at Ross who received substantial scholarships from lower-ranked schools. They were able to negotiate with Ross to get some $$, but from my limited sample, Ross didn't match the full amount. Some choose to go to Ross, others will go to the schools with better funding.
post558169.html#558169 - a compilation of b-school interview questions
8-66345.html - my (detailed) gmat debrief