I think there were too few people wearing no-touching tags to make them work (well enough). At some point I freaked out and everyone who saw me in distress and wanted to help just hugged, patted and generally invaded me - ignoring the tag and the semi-obvious reason for freaking out.

What I do not agree is what you call the ironic status of those tags. I talked to some people about it and aside from straight "I want a lot of hugs" and "don't touch me at all" there was also the opinion "I don't feel comfortable being hugged (or touched), but I can hug some of the other people" - a middle ground, which didn't have a separate tag and did not truly fit neither of the present tags. Given the generally cuddly atmosphere picking a "don't hug me" tag was the sensible action (because not picking a tag would simply put you in the majority - "hug me" group).

I don't know if having a new middle-ground tag would fix this problem. Maybe it would be ignored the same way that the "don't touch me" tag was. Maybe it simply would work better if the group was more balanced. I caught myself several times looking at somebody's tag to check if they will accept a hug and preparing my body for a hug before my brain processed the meaning of the pictogram - since almost everyone wanted hugs, this person must want them too, right?