I play sessions in big Nashville studios like Blackbird and Darkhorse(not country usually), they pay me to do it, not the other way around. How do you know what someone has in their "home" studio? It could be $200 invested or $2,000,000.
I personally own a full production studio at my house with two HD2s with 96khz a/ds, a Studer 2", a Neve 24 track w/1073s, a control24 for mixing, Tannoy and Event monitoring, and about $60,000 in mics and outboard stuff. Plus the control room, live room, and iso booths were built for sound quality by a company I am a partner in.
I could pay to play at a large studio whenever I want, but why do that when I can make money?