You don't seem to understand, that a sellout isn't 41000 tickets sold. You simply can't fill up the stadium completly, seeing that you need some sort of barrier between the two sections of fans, which obviously will take up a number of seats.
A barrier would't empty 4k seats.
The away section wasn't full(it probably never will, no strong travelling fans culture in Italy) and there were some empty seats in the other sections, which probably means that quite a few season ticket holders were not there.
For next season, they need to:
- Reduce the Away section to 500 or 1000 seats(from 2k)
- Find a way of redistributing tickets of season ticket holders who don't attend a game
- If we qualify for the CL and bring in some good players, our attendances will rise.
For this season, I expect an average attendance of about 36k, which should rise to 38-39k next season if the above is done.