Nice question and one of the things we need to focus on if we want to build a community.
DataGrid Blockchain and DataGrid Token ($DGT) are designed to only succeed if there is an actual economy that can be built on it. By creating a way for businesses to create a business account on the DGB and in that account have every inventory item intrinsic to it with the enablement of transferring that asset to another account, i.e. automobile manufacturer transfers title and a containment tree (all attributes of that specific automobile) to the new owners account creates a much more efficient an accurate auditing systems for warranty and other needs.
Although there are no intermediaries of custodians needed in the DGB for settlement, this does not mean a stock/securities broker will not be necessary. Someone needs to scan the decentralized marketplaces to find the opportunities for you, unless you will be giving up your job to be a day trader, you still need these types of services.