It says in the Gemara that one who buries his nails is a Tzaddik (he did what he should, to avoid a pregnant woman from stepping on them) while someone who burns his nails is a chossid (Tosfos explains that burning parts of one's body is dangerous, yet he is willing to hurt himself to make sure that the nails won't be uncovered).
Yet there is a Gemara (mentioned in the Mishna Brura) that if one moves the nails, they don't cause harm anymore.
Why should one burn his nails when he can move them (doesn't harm others or yourself)?