I can say that I have bunch of those and sometimes you can't do anything with them. I could burn tokens but why wasting ethereum, it is not that tokens are taking space or anything. And I have lots of dead altcoins which I bought years ago and they are sitting there. Few tokens which are not worth selling at the moment for few dollars because developers said they are developing project so they will remain in wallet for long time, maybe they will worth hundreds when they release products or they will also remain worthless if developers are only talking not developing.