Potential other uses for blobs in Proto-Danksharding other than rollups

Just something that came up reading about 4844.

I checked out domotheus' blog where he mentions:

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The humble blob begins its life when someone (presumably a rollup sequencer) signs and broadcasts a new type of transaction, aptly named a blob-carrying transaction.

I've seen this a few times. The EIP and other discussions often say things like "rollups can use blob space if they want", but obviously there's nothing stopping them using L1 calldata and just having users pay extra for it.

Was just curious:

1. I am assuming the major rollups have already indicated that they will migrate to using blobs for calldata vs l1 calldata? Is that the case?
2. Has anyone considered alternative use/abuse cases for blob storage that might come about? I'm thinking something akin to ordinals for BTC but not sure what that would mean in the context of ethereum.

Apologies for the somewhat vague question, just curious and interested to hear some takes.