(Yes, going to a conference can be inefficient/terrible way of spending your time. It doesn't prove anything.) There are ways in which conferences fail. There's too little time to talk to other people, especially if they only came to make their report and then leave; you can't count on them accommodating you. (And if you want them to show you how they do things, it is even worse, so just plan it ahead.) There are sometimes lectures which you would not learn anything useful from, and you skip them without remorse, but you don't go to a conference just to skip stuff. There are people who will be less useful to you than you are to them, so what? It is good to be actually needed and not just cited. There are people who strongly disagree with your lab's approach, and they might not give you coherent feedback - that just means that you should write to them later.

I mean, yeah, it's not ideal, so what?