There are some misconceptions about Zartoshtians (correct form of Zoroastrian. Zartosht lit. means golden star or golden camel, his family name was Spitmaan) among non-Zoroastrians.
One of them is that some think Zoroastrians worship fire or soil.
But, they simply respect environment and try to avoid polluting the nature.
They do not bury their deads but put them in 'Dakhme' (lit. means a hot place, although Dakhme refers to a place deads are put but maybe Iranian, just like their Indian brothers, burned their deads in the past). Their philosophy is that burring pollutes the soil and earth.
In the past, when providing fire for homes was a difficult work, people built some buildings called Aatashkade (lit. house of fire) and its usage was just like a well for providing water. People of the city came with a piece of wood and take fiery wood to their houses for their daily usages. So, they use to respect and not worship fire as a useful tool.
However, after that, some rituals added to this works and some symbolic works invented. But, they do not and never worshiped fire.
Their divine scripture is not Avesta or Zand-e Avesta (Zand means exposition) but is Gatha. Gatha is a small part of Avesta, other parts of Avesta has only a religious value among Zoroastrians but they believe only Gatha is from Zartosht himself (today, researches do not confirm the authenticity of Gatha or Avesta as an original book).