We also use some of the previously mentioned visualization technologies and get generally poor results by all measures.
If AirBNB has a few engineers around who are part of solving a unique challenge AirBNB has, then they are probably getting a better deal than we are. I'd wager their productivity per resource is significantly better, not to mention licensing, infrastructure and control over product features. That said, not everyone is AirBNB and has the ability to attract and retain that type of talent.
I'm not saying that you wouldn't choose a good open source alternative if it exists. I'm saying that you shouldn't run off and implement something that exists commercially if your only reason is that the commercial thing costs money.
1. Our problem set is not novel, we're more or less like many others out there and collectively we are a market that a vendor can build a product for
2. Since we have significantly more revenue than a startup like AirBNB we can rationalize and amortize an ongoing expense
3. We actively try not to do things that aren't our core competency
4. Even if we wanted to we have plenty of human resources but not the talent to build our own analytic DB or data visualization tools
I think AirBNB is likely a much different company than most. Their approach to talent attraction/retention, novelty of problem set, ability and tolerance to make a multimillion dollar capital investment in analytic database and visualization tools, etc, etc. In their case the upstart cost of building a custom thing and the value prop likely makes sense.
Building a community can also help distributing the costs. But more importantly it's a labour of collaboration instead of a client/vendor struggle.
But if you find this to be a frequent occurrence, you're almost certainly evaluating costs incorrectly.
You do realize that this is probably THE reason to open-source a piece of custom software after you've built it, right?
...I imagine that they expect the community will do X% of the maintenance work now, so they can save Y%, so win-win for both the company and the community. Also, you increase the probability that any new hires will be at least mildly familiar with your in-house stack if you open-source some of it (think TensorFlow).
Free as in beer is the best answer when you have reasonable expectations that the community will really embrace the product and you'll get back "free as in beer" upgrades and bugfixes to the software you won't otherwise have the budget to properly maintain (and properly document, btw! think of all the free tutorials that will be written for this after it gets popular!) :)
This is why you never try to target developers and if you do, you have to make sure the initial cost to use it is negligible. This is what Atlassian does very well, with their pricing structure.
In the past, I developed in house tools for massive Enterprise companies and the common theme has always been, we can do it better and cheaper. Sometimes that's true, sometimes it's not. I noticed this trend slowly tapering off before I left to start my startup and this was due to the availability of better open source solutions.
Technical people always overestimate what they are capable of, present company included, and if you are set on selling to developers, you have to make sure the barrier to use is negligible. By at least trying, they will either come to the conclusion that what you have created is a piece of shit or they realize it's not worth their time and effort to duplicate/maintain.
Free as in beer is never the answer. A project like this takes multiple engineer-years to build and maintain. That's hundreds of thousands of dollars, at least. How much is a site license? Are you sure? Have you negotiated the rate?
Even for "expensive" services, buying it from someone else is almost always cheaper than paying someone to maintaining it yourself, because expensive services are usually expensive for a good reason: they're niche, and finding someone with the expertise to build it is expensive. And having the source is for a product so that you can customize it is certainly a better answer, but it rarely happens, in practice. It's why we have gobs of open-source Apache-foundation products that nobody in their right mind wants to host in-house, unless they absolutely have to.
Developers have a real, well-documented resistance to paying for things, and it sucks. Because in reality, most development of open-source tools happens when someone gets paid to maintain the tool. If they don't, the tool falls into disrepair. Open-source software isn't free -- it's just paid for by someone else.