It's almost a certainty that a model as good (or better) than Alpaca's fine-tuned LLaMA 7B will be made public within the next or two.
And it's been shown that a model of that size can run on a Raspberry Pi with decent performance and accuracy.
With all that being the case, you could either use a service (with restrictions, censorship, etc) or you could use your own model locally (which may have a license that is essentially "pretty please be good, we're not liable if you're bad").
For most use cases the service may provide better results. But if self-hosting is only ~8months behind on average (guesstimate), then why not just always self-host?
You could say "most users are not evil, and will be happy with a service." Makes sense. But what about users who are privacy-conscious, and don't want every query sent to a service?