I'm not a Spotify user at all now (free or paid). But I do occasionally consider signing up. I have over 200 GB of my own music available both inside and outside my home via a media server just as conveniently as Spotify, but this doesn't give me any opportunity to discover new artists.
But like any subscription service, I'm going to want to know what the value of the recurring monthly fee is vs. my free locally-hosted music now, and a company increasing the price for no reason than to make shareholders happy isn't going to attract my business.