I think Adobe's primary market focus is people who need it for their work. Assume that you're paying a creative person $60-80k+ per year, before benefits; how is $500/yr for their most important tool not a no-brainer?

There's a long term risk of another company building market-share with younger or poorer designers, but that's small, especially with how light-touch they seem to be with piracy. (Torrents of the Adobe suite are trivial to find, and have been online for years without disruption.)