Ack. Sadly, enterprise procurement is all about avoiding blame in case something goes wrong.
Another issue is contributing to open source projects. I know a case where a customer's in house developer had to wait two months to contribute a few lines patch to a open source project because legal objected. They never dealt with that situation before.
Enterprise procurement is all about avoiding things going wrong, avoiding blame is a distant second. When every hour of downtime costs hundreds of thousands, the ridiculously expensive, 24/7 SLA supported enterprise solutions don't seem so overpriced anymore.
That's how at least one of my start-up experiences wound up. The large enterprise entity who'd committed strongly to the product ended up bringing much of the development effort in-house, for several years.
You've got to realise that for enterprise software, there's $10 sales, $100 sales, $1,000 sales ... and then $1,000,000 sales. At the top level, you're looking at entities who have the resources, and occasionally the motivation, to bring product entirely in-house. It might not be their first choice, but it's an option, and quite likely something they've already considered when negotiating for services.