The Creeper makes no sense

I decided to watch this knowing the director's disgusting background, and I honestly was liking the first 15-20 minutes a lot. Like more than I thought I would. But the film starts getting really stupid after the first act and by the end it's just confusing to me.

1. How does the Creeper have time to soup up his truck? If he is only awake for 23 days at a time, surely he has no time to be a mechanic. I've seen normal cars spend months in the shop at a time for pretty general transmission replacements or engine swaps. It would take months of constant work to get the Creeper's truck to where it is. By the time he goes back to sleep, 23 years would pass and the truck, which has been sitting and rotting under a tree or something, would need to be completely refurbished.

2. Why does the Creeper even need a truck to begin with? Some have said he uses it to startle drivers so he can smell their fear, but isn't he a gargoyle demon? Can't he just fly up to people and startle them just the same? Some have also said it's to transport his victims, but he also has super strength so I don't see why he couldn't just pick up multiple bodies at a time.

3. Why does he constantly go after new victims? Okay, so he kills one person on the first day and takes their body. He should be good to go, right? Why keep attacking people and replacing his already new body parts with even newer body parts? Couldn't he just chill in that church for 23 days? Or is the Creeper just a sociopathic monster who enjoys murdering purely for pleasure, and just happens to need body parts at the same time? Maybe Jeffrey Dahmer would've loved to be resurrected as this thing.

4. What happens if someone discovers him or his lair while he's asleep? The odds of a building in America not being explored for 23 years sounds pretty unlikely.

The movie would've been much better had the Creeper been a normal villain, maybe with some sort of supernatural abilities that would still make it reasonable to drive a truck. The reveal of making him an inhuman demonic bat creature ruins pretty much all the buildup from the first half. The film should've started with two curious teens discovering the church, only to find out the killer is a demonic monster, or keep the first part with the truck and make the killer a human.