First, the reactors are consuming the fuel while deployed, but no waste is stored at the sites. It is stored centrally so there are a few centralized sites that hold the waste for a few hundred years. After which you could make things out of the material and use them around your home without issue.

The reactors cannot be deviated for nefarious purposes. And the materials are not less secure. The materials are being consumed by the reactor, and they are not dangerous as they are. In fact these reactors could destroy weapons grade material that is slated to be destroyed for fractions of the cost of programs the US is pursuing. Plus the reactors are secured when deployed. They are also buried and completely cooled by natural forces so they always stay cool. No fuel overheating.

The reactors cannot be hacked, and if a bad actor commandeered one, all they could do is turn it off safely. Even if they tried to make it hotter it would just turn off and cool down. There just isn't enough fuel in the core to do anything else.