Just about every side in the SPL is only a kick-in-the-arse off extinction. There is no way any of them would vote anything through that resulted in a loss of income - be it more teams in the league (less OF games, less home games) or summer football (contentious I know, but I don't see TV companies paying more for this as some suggest - I wouldn't pay to watch Scandinavian games during our summer for a start). If anything I think we'd get less exposure with summer football.
Also, football is a winter sport and postponments are part and parcel of that. It's not like we live in Russia, or Scandinavia where it is impossible to get games played in the depths of winter, and there is no predicting when we'll get the bad weather. I've seen snow in April and tree splitting 10 degree sunshine in December.
Finally, when would we relay the pitch / do much needed groundskeeping work (I'm at the absolute limit of my knowledge here) if we were playing on it all summer?