NO, THERE IS!
Muhahahahahahaha!
Proof:
Noun adjuncts were traditionally mostly singular (e.g. "trouser press") except when there were lexical restrictions (e.g. "arms race"), but there is a recent trend towards more use of plural ones, especially in UK English. Many of these can also be and/or were originally interpreted and spelled as plural possessives (for example "chemicals' agency", "writers' conference", "Rangers' hockey game")
[2], but they are now often written without the apostrophe although this is criticised by some authorities.