For the same reason SaaS is popular in general: yes, you could get a VPS, install all the needed software on it, keep it up to date, oor you could pay a company to do all that for you.
Nowdays LLM can be ran on consumer hardware, so the "dead battery" analogy fall short here too.
For the same reason SaaS is popular in general: yes, you could get a VPS, install all the needed software on it, keep it up to date, oor you could pay a company to do all that for you.