Spotify took something that previously cost money and made it free with ads.

There's also the fact that people can view Spotify as a ongoing service easily while people view MS solitaire as a component of a product. Normal people dislike when you turn their products into services needing ongoing payments

"A one month upgrade will run users $1.49, while a year-long upgrade costs $9.99."

I'm personally used to pay only one time for a game (except perhaps for MMOGs, where a subscription really makes sense).