Dropthings database storage problem

Jul 7, 2013 at 7:46 AM
dbo.WidgetZone row count 792227 57MB
dbo.ASPNET_Profile row count 131627 101MB
dbo.aspnet_users row count 131656 51MB
dbo.widgetInastance row count 1729456 197MB
dbo.aspnet_membership row count 44 0.023MB

my dropthings website only have 11 registered users.
But the problem is that the dropthings database is exceeded 500MB on the storage.
Total visited count for my website is less than 2000 and less than 10 visits per day.

I got a plan to make my website for many users more than a million.

How can I handle the storage problem of the dropthings database?