everyone dumps their tanks when they need too :)
but if dinner is happening in full view with people around their table and food is coming out and they are sitting down to eat----ugh, come on, we can all wait a bit and not 'play' with the black tank at that exact moment.
I have to say our stink is very minimal. but for some reason the OP got nailed by high nasty stink :( makes it worse for sure but just seeing people messing with black tanks right near me while eating, well, just the word 'yuck' comes to mind :)
this falls under basic common courtesy to me.