Unfortunately, I don't not believe there is currently any capability within the InfoProvider objects provided by Kentico to support bulk inserts or updates, although I am happy to be corrected.
The info objects typically map directly to a database table, so it would be possible to leverage another library to make these changes directly. I would strongly recommend against this approach though, as circumventing the InfoProvider would mean that any additional code or events related to the setting of a ShoppingCartItemInfo would not be triggered.