The risk is the same : to trust your money elsewhere than on the blockchain. The schemes to deceive people into doing so might increase in numbers with sidechain but the risk is the same.

As for your second comment, I'm sorry but they absolutely should understand it. It is the very principle of Bitcoin : creating a trustless environment. It took a long time for Bitcoin to establish this status and it should be obvious that any step outside of its circle exposes you to risk that should be accounted for.

Also, I have some difficulty with your proposition that "ordinary people" will be trusting their money to all kind of obscure sidechains. Ordinary people only trust mainstream and established platforms. It is very unlikely the majority of them will fall victim to overlycomplicated schemes.