We have seen Arenanet capable of adding stuff like the flying carpet or the broom and those are even mobile.
why not add chairs (stools, kitchen chairs, armchairs, couches for diversity and maximum money generation)
to the gemstore.. you could make these items cost basically anything and they would sell either as a status symbol (“look at me i haz a credit card”) or for roleplayers…
the furniture and tree tonics prove they are able to make you immobile so as to not have people flying around in armchairs if that’s even an issue