Burgess dwarf food infested?

[cookietiger]

Today when filling my hammy's food bowl I noticed loads of small bugs are in my Burgess dwarf hamster food I've been using this bag for a couple months now but I never noticed this.
I'll admit when I first opened it there was a tiny tiny little spider but I thought nothing of it. Now theres dozens of these tiny black bugs and I think other bugs too. I use a a food clip to keep the bag closed so I don't understand how they might have gotten in.
Has anyone else had this issue?
I'll probably go back to using pets at homes hamster food and throw this bag out.