I remember the old days when I spent hundreds of hours on casino chats just to get some rain. Because I had no money to deposit there or did not want to spend my money on casinos. But I wanted to play and used the free money to play there. So, it's important for someone to unblock their chat so they can get the benefit of it. But, these kinds of players are not important for the casinos.
You summed it up nicely. Besides the amount of time you are wasting, you can use it to do something productive. You are not making money nor even having entertainment.
I've been doing the same thing and yeah, you're right it's a total waste of time, especially if you don't get any chat rain of what you want. But if you're lucky enough to get some $ in chat rain and turn it into a decent amount, that's a different story. I did manage to withdraw twice from some online casinos without making any deposits because of the chat rain. So it doesn't always a waste of time for me.