No, they can't; artists are between a rock and a hard place w/r/t Spotify, because if they aren't made available on one or more of the major paid services, they (a) are pirated merciless and (b) have to compete (and inevitably fail) for the promotion and monetization of their own work with services like Youtube.
I'm not saying Spotify is uniquely to blame for this situation, only that they're a part of the situation.
I'm not saying Spotify is uniquely to blame for this situation, only that they're a part of the situation.