I hear ya. Its a bummer that we can't offer all divisions this year. There's no Grandmasters either. So you are not alone.

And in terms of the ladies, they will always be welcome.
Now to answer some of your questions. At the crux of the matter is that we have one 18 hole course to work with. We are also competing with a half dozen or so festivals that happen during this time of year right across the street at Speedway Meadow. This is very limiting. In addition, the city has denied us our traditional 18 hole safari course ever since our permanent one went in. I think we are very lucky to even have a tournament this year let along permission to use the extra holes for this year's event. Otherwise the field would have been even smaller or not happen at all. And to uofc2003's observation regarding the NorCal events that have had large Am fields while being a Pro/Am weekend, 3 of the 4 tourneys have two 18 holes courses. They can accommodate 144 players.
In terms of how we decided on the format. This was voted on by the Safari staff that was present at the first meeting earlier this year. There were 2 options put on the table. Am only or Pro/Am. Pro/Am reigned supreme this year with the compromise to limit the number of divisions. The pros have not been able to play the last two years so i think this is an ok compromise. Not ideal. But ok.
In terms of the bigger picture, the SFDGC is dedicated to maintaining and expanding disc golf in San Francisco, ie. McLaren, and we need your help to do it. Once we have 2 courses in place, you can bet we will host one the best of tournament weekends in the NorCal Series. But until then, we need everyone to be patient and supportive of what the SFDGC is doing for disc golf in the city.
Todd