I don't know if Barcelona is going to play a very sweaty game against Villarreal because they have already secured their position in the league. so I don't think this match will have any importance to Barcelona.
Maybe it's true because whatever results Barcelona get in the match against Villareal will have no effect on their position in the standings. But you certainly know that a team like Barcelona always think that H2H and their record against other teams is still something important to maintain, so defeat is something they will avoid Villareal.
But of course when someone wants to bet something on this match then I think the risk can increase. I believe Barcelona probably won't lose, but a draw is still very possible.
I don't think Barcelona would take the game lightly even if though they've secured the 2nd spot, but that said it's going to be tough game, but I don't Barcelona would play to lose and it might be worthy of a bet on Barcelona to win.
The same can't be said of Real Madrid who still have a champions league final coming up, I'd expect Ancellotti to rest his best players or give them a very limited time of play.