Airlines play the WX card to get out of giving hotel or food vouchers. It's not just the low cost carriers, Delta cancelled on me a few months back out of JFK. Landed, got a ride to the terminal, checked my bag, walked to the gate, the flight was cancelled. I asked about a voucher, the agent went behind the counter and came back and said it was a WX cancellation so no voucher.
I pointed they still had 32 flights leaving that evening but all she could say was I was rebooked on a flight the next day. The nearest WX we saw coming in was in Pennsylvania. I figured the outbound crew was going to time out.