I've not been able to find what they were charged with beyond the robberies.  It's possible there were legitimate weapons, assault/battery or other charges that came with the theft charge, and they added up accordingly.  The event happened during the "three strikes" era, so it's also possible they hit their maximums due to that.  Still...nearly a century for video store robberies seems out of place even given those possibilities.

I do know this much - if it had happened in Baltimore, the judge would have asked what movies, if any, were stolen...and given them a more harsh sentence if they weren't decent films.