No, it's not mishandling. It's not a mistake, it's not malicious, you just don't know how they're going to use it. "Mishandling" implies some sort of breach of

No, it's not mishandling. It's not a mistake, it's not malicious, you just don't know how they're going to use it. "Mishandling" implies some sort of breach of trust or contract, but in this case you didn't realize what you were agreeing to when you handed over your data. They're handling the data as they've always intended.