In one word or less: No. Haha
The
Disney Dining plan at DL is nothing like the one at WDW. Of course it's nice to have the "pre-purchase" option of the vouchers, but, you could technically LOSE money since it's dollar for dollar.
For instance, if you use a $5 voucher to buy a $3.75 pretzel, you don't receive change. If you go over the amount of the voucher, then you have two options, pay in cash for the overage or use another voucher (and still not receive change).
It's not like at WDW where you have "snack credits, counter service credits, ect". It's vouchers in dollar amounts.
What you may want to look into is pre purchasing some character meal vouchers through a couple of places. I think Ares Travel is one (don't quote me on that though), and there is another place that sells them.
Hopefully some Disers will be along shortly to give you more specifics.