It’s not about prices but about amount of these available. Just like legendaries or precursors, less of them on tp = bigger prices. I see no reason why all fused weapon skins from flame & frost, all wintersday skins from X-mass, all sclerite skins from southsun and all aetherblade from sky pirates are available and only last year’s halloween skins are not. Heck, even this year halloween skins were added.
I dont see a reason why old halloween skins shouldnt be re-released along with all the rest. The price in tickets could be high (7 tickets for fused skins, so maybe 10 for halloween) but it would be available for players like me, that didnt have played since release and waited whole year for this occasion.