You can save up your Tears for Master’s Blood, you can save them up for showing off, you can use them to fund a wedding (313 progress/bottle).
It can also gain you 1 PtPT: ToL up to 11 and +5 Melancholy.
(They also cost 7 PtPT: ToL in the Nadir + some Irrigo)
If you’re trying to get the Spire-Emporium at Neathmas, it’s absolutely essential. There simply isn’t enough snow, otherwise. Get as many as you can, before next January.
It’s quite possible to get the Spire-Emporium (AND the Sanctum AND the Suite at the Royal Bethlehem) without spending even a single Vial of Tears.
It’s even more trivial if you have any ToL saved from a past year, but it’s not necessary.
The Spire-Emporium itself requires only 9 ToL. You can get there with just two Pails of Snow by making the right choices with Mr Sacks which give you ToL boosts.