"£Free" is rarely £0. It usually means "£you do some of the work yourself and we indirectly profit due to metrics/economies of scale/network effects/data/kudos".
I don't think that's the trick at all. Running up bills will only make people leave for other services once their business does get money flowing.
Instead, I believe the reason cloud companies give away free stuff is the same reason Microsoft will give away Windows upgrades to students: if their weird, proprietary API is all you learn, you'll only be able to get started quickly on their platform so the moment you need to pick tech for a small business/your startup, you'll be quicker to choose their service.
There's a reason AWS Lambda (and Azure's competitor) is free but OpenStack/vSphere providers expect you to pay off the bat: if your workload and knowledge transfer (relatively) easily, there's no lock-in with which to trick people into choosing you.
Instead, I believe the reason cloud companies give away free stuff is the same reason Microsoft will give away Windows upgrades to students: if their weird, proprietary API is all you learn, you'll only be able to get started quickly on their platform so the moment you need to pick tech for a small business/your startup, you'll be quicker to choose their service.
There's a reason AWS Lambda (and Azure's competitor) is free but OpenStack/vSphere providers expect you to pay off the bat: if your workload and knowledge transfer (relatively) easily, there's no lock-in with which to trick people into choosing you.