Many of these were still in their packages - purchased, no doubt, in a store's pet department or even in a specialty pet store. It's probably a bit surprising and certainly a bit of a disconnect to think that products made for cats and dogs aren't safe for them. Yet that is often the case.
Why would products made for pets be unsafe? Many pose a choking hazard. Thankfully, this is an easy problem to fix.
When purchasing a new toy, examine it for small attachments that are of a size that could be swallowed, or are small enough for them to choke on: mice might have small plastic eyes attached, wand toys might have bells. Balls might be wound with yard that can come unraveled and ingested.
If you see such attachments, clip them off and you should be good to go.
In addition to choking hazards, some "classics" can cause major medical issues if ingested.
Who hasn't heard of the classic 'cat playing with a ball of yarn'? Unfortunately, yarn, string, twine, rubber bands, thread and other such items can cause intestinal blockage or perforation - both of which are life-threatening issues.
I know this firsthand. Years ago I'd left my sewing machine out, along with a dress I was mending. Ryker's older brother, Caleb, decided to munch on the spool that was threaded through the machine. I didn't notice - and three days later when he became listless and stopped eating, the vet discovered the thread had perforated his intestines in almost a dozen places. He would have died without emergency surgery. Needless to say, I am extremely cautious now when doing that rare bit of sewing or knitting (since I'm not that crafty a person Faraday, Max and Allie are fortunately pretty safe around here!).
If you ever do see a bit of yarn or string coming out the back end of your pet, please don't pull on it - that might cause intestinal damage as well. Best to have it checked out by your vet to ensure it's properly removed without harm to your dog or cat.

If that seems a bit extreme, consider this: not only can feathers be ingested and cause intestinal problems, but some cats like Faraday are extremely enthusiastic in their play and will run madly through the house holding a wand toy by its feathers and completely ignoring the 2 feet of stiff plastic handle protruding out from it.
There have been times we were afraid he would impale himself on the wand part of the toy if he was unsupervised - he's just that fast and energetic!
We don't mean to scare you away from playtime - it's a critical element in your pet's health and can provide both physical and mental stimulation. We're just suggesting you might want to use caution when choosing the toys that you'll leave out while at work or when going out of town.
We personally can't think of another single toy that has caused more excitement around our house (and burned more kitty calories, too!) than feather wand toys. No, we don't leave them out unsupervised, but we get them out every day. And if we forget, either Faraday or Maxwell can be found camped out on the counter right above the drawer where they reside. Usually looking at us plaintively until we cave and drag out Da Bird for 30 minutes of non-stop romping.