Umm... no one at the feed store is going to buy "The bugs were in the bag when I bought it" story......mainly because that is rather less common than storage problems.
Point being, this poster stores her feed in a container that is not sealed and will not stop insects from entering.
Blaming it on the feed company, as some have done, is silly....considering her poor storage choice.
I'll say it again: garbage cans with lids ARE NOT bug proof in any way. insects LOVE to crawl up under the lid and invade what is inside.
IMO, the bugs likely got in her can. And they will continue to do so no matter how many bags of feed she buys.
She needs to find a sealed container to store her feed in. SEALED being the key word here, not just something you throw a lid on.