Yes they can. There's a name for that: shadow IT. All of a sudden you realize that the annoying engineers have stopped annoying you not because they become better people, but because they got the credit card of some VP and got their own platform on AWS.

Is it really "shadow IT" if they got approval from the VP with credit card attached? Seems like they're officially accredited to do the work.

Sure is, the VP is VP of Marketing and he puts the expenses under media research or something, and they put the whole company CRM data into Mongo or Elastic on AWS with no auth, open to the whole internet to see. And sadly that's more daily news than fiction.

This.

The things I've seen built with Excel and Access.

That's why the analogy is more akin to a local governmental services.

100%. This is why it's leadership's job to align incentives such that teams are motivated / rewarded for providing other teams with a high-quality service.