Bugs and mice will get into anything they find edible. Mice and rats LOVE peanut butter. It will work better as bait than almost any sort of cheese.
There is a stipulated maximum number of insect parts roach turdlets and rodent "pellets" that can be in most foods without it being banned from the shelves, It is a small, number, but is is not zero. Perfection, as always, is nearly impossible to attain.
There are basically two kinds of peanut butter: the creamy smooth type that has hydrogenated oils in it, and the all natural kind, in which the oil tends to separate. Both kinds come in smooth and crunchy. Read the label.
If we had no regulations, there would be nothing about content on the label.
My favorite fraudulent product is the brand Juicy Juice, which claims to be 100% juice.
It is indeed 100% juice. But about half the juice in 100% juicy Juice Cranberry juice is apple juice. And of course, apple juice comes from where? Michigan? Washington State? No, China. Not that Chinese apple juice is bad for you or worse than American juice, just that they are selling a product without most customers becoming aware.
You can no longer buy a half gallon container of orange juice. They are now 59 ounces, not the 64 that would actually be a half gallon. When there was a freeze of the crops several years ago, Tropicana conspired with the other producers and they shrunk the containers.
You have to read those labels if you really want to know. They have the technology to make stuff that tastes like any sort of juice you might want without a single bit of fruit being squeezed or harmed in the process.