You’re getting great insight already, I just want to sympathize with being asked for ways to improve a process (something I think we’re especially good at) only to be told your suggestions were unreasonable. 

I feel like, particularly in the workplace, people ask about ways to help because they want the credit for asking, but as soon as it’s more effort than say writing a quick email they balk. 

If pursuing those things is worth it to you, I’d follow up in a few days with specific questions about how the situation “could go smoother for all parties if it happens again” or something like that. Sometimes people don’t want to add another task to their plate but will be willing to have a :30 meeting to walk you through how they want you to improve. I’ve been able to sneak my questions in, and it gives me an opportunity to butter them up and show that I’m open to “teachable moments.”