You can ask for as many as you want. If the whole Corporate allocation is 150 (which won’t be far off for Bournemouth) you can theoretically ask for 150. Obviously won’t get them though but if amazingly no one else in Corporate had asked for any then you would. In reality that won’t happen and if demand exceeds supply (which it did for Bournemouth) then initially everyone is limited to 2 (whether you own a box or a seat in Joes) and then they either ballot or give what’s left to those who pay most for their home corporate
Which would indicate it wasn't corporate that are to blame. So why were their empty seats ? One thing I would say is perhaps we as a fan base are very quick to slag off sections of our support with little evidence. Points Whores, Supporters Clubs and now Corporate have all been blamed for abusing the system and yet it may well be that none of those 3 are to blame for more than a handful of tickets.