Sounds like sending emails is wasting everybody's time. But not a lot of resources. And that's a problem with email: wasting other people's time requires very little effort. It's efficient for you to send the same email to 100 clients. You get a 100x return on your effort. At best a responding client gets 1x return. The average case for your clients is a negative return because they have to deal with your email even if they don't respond.

That asymmetry -- valuing your own time more than clients -- is intuited by most people. You're sending emails and expecting people to go out of their way at your request. It's convenient for you and inconvenient for them. It doesn't express an appreciation for their business at both levels. Their business with you and their business as a set of operations with a set of problems.

I'm not suggesting visiting every user all over the world. I am suggesting that a good way to understand what your users are doing is to see what they are doing. Visiting makes it easy for your users to show (not tell) you what they are doing.