nope. the maps program DOES run off a data connection.
no maps are cached in the pearl on arrival that i know of. i know that if you do use the pearl to browse for maps it will cache a bit of them. you say that you dont have a data plan, but did you have one before when you first got the pearl and you used the bbmaps program then?
one last solution. when i first received my pearl i didnt have a bbdata plan either. in fact i even had my carrier ban all data usage for me because i used to accidentally open the mobile browser on my previous phone. but for SOME REASON when i first got the pearl i opened the bbmaps application and it worked! i couldnt browse the net or get email because, as i mentioned, i didnt have a BB data plan. BUT bbmaps worked. maybe bb enabled it in such a fashion that it will work off your standard pay-as-you-go edge/gprs connection, not needing BIS or BES. and as a result your bbmaps worked and you will be charged by your carrier for the data on a pay-as-you-go rate.
id check with your carrier. because it MUST be using data to get the maps.