These are very interesting propositions. California have basically been thrust in the middle of tribal strife between Native American tribes. These propositions are referendums, which means that the State Legislature already passed them, and the governor has already signed them. Rival Indian Tribes (and 2 race tracks) spent enough money to raise a referendum, knowing full well that when voters aren't sure about a proposition they tend to vote "no". When in fact, the default action on a referendum should arguably be "yes".
At the heart of these propsositions are casino expansions (roughly tripling the amount of slot machines in 4 casinos). Assuming the voter information guide is objective, there is absolutely nothing shady in these deals as they stand. California stands to reap a good amount of money through these 4 agreements, with arguably little disadvantages.
The main problem I have with the "no" argument is the false claim of environment damages. There is absolutely no environmental impact of these agreements over and above the impact of any business which draws traffic and visitors. I care about the environment and I don't take lightly to crying wolf. And with that lie, they have lost all credibility.
In addition, for the increased strain on local infrastructure which larger casinos will create, local governments are explicity allowed to negotiate agreements (ie fees) for maintaining roads and paying safety officers in the effected regions.
These compacts are simply business deals between the State of California and the Native American Tribes. They benefits both parties substantially. Particularly when the State of California is in debt and raising taxes is suicide these agreements would be a welcome income boost. Besides, like the lottery, this is really a tax on people who are bad at math (the gamblers).
If the financial backers of these referendums main complaint was that these compacts unfairly benefitted 4 tribes for illegitimate reasons, I would consider voting no. But because they are liars, I'm voting yes.