Interesting uses for Illusionist's "Phantasmal Creatures"?

Illusion Wizard gets the following subclass feature at level 6:

You always have the Summon Beast and Summon Fey spells prepared.

Whenever you cast either spell, you can change its school to Illusion, which causes the summoned creature to appear spectral.

You can cast the Illusion version of each spell without expending a spell slot, but casting it without a slot halves the creature’s Hit Points. Once you cast either spell without a spell slot, you must finish a Long Rest before you can cast the spell in that way again.

It's cool that I get those 2 spells Always Prepared. But they require costly Material components, so that got me thinking: If I'm going to spend gold on the material components for those spells, would I want to spend them on a spectral beast/fey with halved HP over a normal one? (The spell slot aside.)

So I've come to you fine people. Do you have any creative ideas for a spectral Summon Beast/Fey over a normal one?

The only thing I could think of is that maybe my enemies would see a spectral creature and assume it was an incorporeal illusion and thus couldn't harm them, therefore lulling them into a false sense of security. Or is that a bit far-fetched? (I'm new.)