Re: Question about seats
I think it is the seating capacity initially, if pontoon was marketed for cruising; allowing the maximum number of passengers. The ones marketed for fishing generally have pedestals there. I do suspect, that if you, or I for that matter, decide to put in those pedestal seats, additional bracing would be called for. Possibly someone on this forum who has that setup can advise what was used to support the reduced weight distribution of a base. I know you would want to catch at least two deck supports to keep them from rocking. I think additionally, the bench type seating is to bring passengers to front, to help balance load. Don't really know about riding up front on pedestals while under way.
