Some have the custom to say the bracha before kindling lights on (erev) Yom Tov. The linked page claims in one place that this is allowed because we don't receive Yom Tov with the bracha, and in another place because "there is no problem of lighting a candle on yom tov, therefore better to make the bracha first [as is customary]." (The first explanation is not sourced; the second is attributed to the Magen Avraham.) I read in my own source that the second of these is the reason.
According to the second reason, shouldn't we then absolutely light the candles from a pre-existing flame--even (erev) the first night of Yom Tov--if we are doing it in this order? (It is prohibited to light a new flame on Yom Tov; however, one may light from a pre-existing flame. If there is any sense at all in which one ushers in Yom Tov with the bracha--as this explanation allows--one would then need to light candles only from a pre-existing flame. One could, for example, strike the match, make the bracha, and then light the candles.)
According to the first, might there be anyway be a reason to light from a pre-existing flame because of marit ayin? (In other words, that others might think one can create a new flame on Yom Tov because this was done subsequent to the bracha.)