Is it just so they can say "not my fault, our project is only using big name frameworks, DBs, etc so I did all I could?"
Or is it because they don't even begin to understand what's going on in the tech scene and just buy what appears to be the most shiny, expensive solutions?
Support is one reason. If your database goes down, they'll send a team of engineers to figure out what's wrong. If they have to, they'll bring in hardware to duplicate your systems, and have engineers working on it 7x24 until they find out what's wrong. Not many vendors can provide that level of service, and if your business requires it, you're willing to pay for it.
I was once in a meeting on site. The task was to get some data from an AS/400 to a Linux server and display it on a website.
Text files would have been enough to cache the data. But you never know how a project can change over time so I proposed PostgreSQL or IBM DB/2. The latter in case they absolutely wanted to pay for a database and they are already using an IBM AS/400. (We were using PostgreSQL and Informix.)
At the meeting they said they have already bought a license for an Oracle DB. Without consulting us. So we were forced to use it without prior experience.
I've had an enterprise vendor offer to drop money into my personal account to make sales. Not naming them, but the sad thing is they actually did have the best product in their space by a long shot. The ones who sucked were probably even better at bribes.
I have seen a high-profile CTO dismissed for just cause because he accepted an invitation to speak at a vendor conference in Paris. When hired, we signed a very strict code of conduct document that prevented us from accepting any valuable gifts from vendors.
A vendor once sent me a mug. I had to open the box in front of a witness.
That sounds like the definition of a bribe, which is a crime. I would advise you to not make this information public or at least public under an account that can be traced back to you.
Is it just so they can say "not my fault, our project is only using big name frameworks, DBs, etc so I did all I could?"
Or is it because they don't even begin to understand what's going on in the tech scene and just buy what appears to be the most shiny, expensive solutions?