How do you guys deal with "actions" in your API's that are not CRUD? Something like reserving an airline seat where you just want to pass in an id of a seat and

How do you guys deal with "actions" in your API's that are not CRUD? Something like reserving an airline seat where you just want to pass in an id of a seat and a user id. I guess that's what PATCH would be for? I was unaware of this verb until today. What I'm struggling with is that REST does not seem to fit with how we use the web today. These HTTP verbs were designed for a document centric era of the web, not for the complex processes we're modeling today. I'm not really seeing REST being easier to design or consume than RPC style web api's--isn't that the whole point? I mean if you were designing an API to be consumed internally in Ruby/JAVA/C# etc, would you design it like REST? I wouldn't. Why have we all become convinced we need to do this for a web api?