Your SN wallet is a lightning wallet not an on-chain one. But because it's custodial, it's not even a lightning wallet - it's a virtual lightning wallet. All users share a single lightning wallet and SN has a record keeping layer for the amounts of each user.

In the future, when we're non-custodial, your SN balance will be your lightning node's balance so there won't be a need to export anything.

k00b

SN release: lightning address support

For me, nothing specifically. But for example, for someone that would like to use SN as their outlet for broadcasting news (like a "real" reporter), I'd imagine they would like to be able to monitor their balance from their wallet app. 