Why are the catch rates on the bugs so low?

Dear Niantic, Scopely, whoever is running the show,

Bugs have always been some of the earliest Pokemon we can encounter in the main series games. Why does a 100 cp Weedle take 3 Pokeballs to catch?

Why does a Nincada take a razzberry and a great ball to catch?

Why do I have to throw razzberries at Wurmples, Dewpiders etc?

I can't believe the amount of balls and berries I've had to toss on these bugs only for half of them to run away.

How is Scyther so much easier to catch than a Caterpie is beyond me.