Did you see this in their FAQ?
Looking at their comparison table that you linked, I have to suspect that this isn't done so that it's editable via Prismic. If I had a client that wanted something like this, I'd create a slice called Table. If the client needed multiple tables, I'd use the variations feature of slices to create the different tables. I'd code the tables as needed. IMHO, this type of data isn't likely to change often enough to need to have it in the Prismic editor.
I totally understand if this doesn't work for your business. Perhaps you deliver a site and then disconnect entirely from the client. This could give you a reason to have them retain you or to contact you again for paid updates. 