Hmm I was looking into this last night for frogger and I think you can attach thionyl chloride with primary and secondary alcohols without the addition of a base. Now the HCl leaves off as itself because it is more stable like that and you have the thionyl group attached to the oxygen. But, dont forget that the thionyl group is a good leaving group as itself with oxygen and this product is usually used for another subsequent reaction as an intermediate.
And yes as Wired said, primary and secondary alcohols only due to steric hindrance.