Absolutely yes, you should work with active campaigns on both Kickstarter and Indiegogo to cross promote each other. Cross promotions were one of the best ways to expose our project to new audiences (we did two campaigns totalling $1.2 million across Kickstarter, Indiegogo, and BackerKit). For our most recent campaign, we raised an additional $1800 that we wouldn't have raised otherwise. We only worked with campaigns who were willing to promote our campaign as well, and agreed to do it for free. For the best results, we only partnered with campaigns that had a similar level of funding and quantity of backers. For example, if we had $100K in funding and 800 backers, we didn't work with anyone with less than $10K in funding and <50 backers. You want to be picky with the campaigns you promote to your backers list; you've earned the trust of your backers since they've paid money to your campaign, and you don't want to refer them to projects that are not fully funded, or look sketchy.

Crowdfunding is not for everyone; if done correctly you can use it to sell anything. The key benefits of doing a Kickstarter project is being able to use the campaign page as a marketing asset to show future investors, potential clients, and distributors/wholesalers (if it's a physical product). The vast majority of top Kickstarter projects and most of the successful projects are all physical products (tech, fashion, boardgames, etc) because of the the inherent nature of Kickstarter being more like an ecommerce store, where visitors browse for new toys and gadgets in exchange for their 'pledge' money. In the case of community projects like yours, it's more challenging to raise a higher amount of funds because your project is not as easy to scale from a marketing perspective; the 'ecommerce' aspect is more challenging because it'll be difficult to offer value to people online who won't be able to visit your Drive in Theatre in person. You can still use Kickstarter to raise funds (I predict most of your backers will be local), and then use the campaign page as a marketing asset to show investors.