Appreciate a lot of the comments here. Let me add a few of my own.
To start, I'm as big a capitalist as anyone. Competition is generally good, especially from the customer's standpoint. Startups should compete hard to create and distribute the right product.
My point here is that I've seen a few startups waste a lot of time and energy beating the crap out of each other, often to no avail. I don't expect these guys to get together and hold hands. I do expect them to take the high road and welcome others into an industry they are also trying to change, especially when you are going against an incumbent who really can beat the crap out of you.
I'm not advocating calling up your buddy at a competitor and saying, "Hey let's band together." That's probably a bit much. I'm referring to the situations like the following:
Say you are RelayRides. A reporter asks you, "Don't you think Getaround does X, Y, or Z better than you?" A great answer to that question is, "We love what Getaround is doing and support anyone getting car sharing into the masses. We hope you choose to use RelayRides because we think it's the best service in the industry, but as long as you're choosing to car share instead of buying a new car we think you are making a step in the right direction."
Hope that clarifies a bit of the discussion here. Thanks for the enthusiastic response.