This way you lose them every time when something goes wrong with the infra, or when your fleet autoscales. Or if you do blue-green deployment with infra, then on every deployment.

Your storage/indexing money spend scales with your company. If you have < 10 hosts you can probably handle logs with a cost that's a rounding error with something like loki+grafana.

If you have a bigger environment and more people, the cost will be more significant, but you'll also likely have more revenue to justify it.