Once they’re using the product they can see their actual usage and cost metering. So they can either extrapolate that to larger scale or test it at scale for a short time to see hourly/daily cost and then extrapolate for the month or year.
In other words it’s not much of a burden and they get much more reliable information.
But they can still do that even if there's a cost calculator upfront. Removing the calculator simply obfuscates the ability to estimate cost with the happy justification that fault lies with the customers who all seem to be bad at estimation.
In other words it’s not much of a burden and they get much more reliable information.