I get packs in everything sent to me, insulin, chocolate etc because of where I live. We hate throwing stuff like that out when I know lots of people that use them all the time. I send a box full off and on to a girlfriend that sends me baked goods and she sends them back with backed goods! I also have left some on a rack at a particular health store that said people are always looking for them. And I periodically ask some people when they are over if they would like some and mostly they have said yes. I know someone off and on that helps with food giveaways at a church and they love to get some.
Be careful about storing some of them forever on a pantry shelf, some last forever but some eventually leak. We have had some in the fridge we have used forever, we have tossed a few in the trash when they did start leaking. I think most of the gel packs here nowadays are non toxic. Do not put them down the sink, they can clog up the pipes.
Lately we have been getting mostly a gel that says it can be used to fertilize plants, I have been warned to find out exactly what is in them though because of possible additives. But the major ingredients are what is found in a bunch of fertilizers, polymers is common, but I don't know if there is a difference in the polymers used. It's becoming more of an issue as people that get meal kit deliveries get a bunch constantly and they end up piling them up or having to dispose of them. So in the US it is becoming more of a thing to be able to do something with them because of waste.
But where I am at, because of our year round warmer weather and a lot of beach going, people are happy to get them as they use them a lot.