The difference would be in how many "fake" support calls one would get. If your internet doesn't work it's probably broken and on the provider, if your cloud is broken you're probably holding it wrong.
The comparison isn't apples to apples, it's 1 service vs 100's (with documentation).
As mentioned, I understand why this is a separate product and I think it's reasonable to pay for support if you need help. There's been some great examples of GCP support bending over backwards to find the most convoluted problems you could imagine. (1)
That'd be worth 30 usd a month to me.
1: https://news.ycombinator.com/item?id=23235995