For desktop applications I just translate the monthly subscriptions into yearly. Most software right now is sold as either yearly subscription or "year of upgrades" so it is one and the same.
If I can't use the software without an active subscription, it is definitely not one and the same. I like Sublime Text's license of 3 years of upgrade with a purchase, no limitation on usage of the software. Unclear (AFAICT from the FAQ) how it would work for CodePerfect 95.
I have some applications that are years old without upgrading to current version. Reason - the old version works fine and does everything I need. However if that's the case I sometimes decide to upgrade at some point to feed the developer.