I totally agree with your comment about the SLA penalty as an incentive to the provider to take reasonable measures to ensure service.

But that's just in general.

When negotiating bespoke SLA penalty clauses, it can be very illuminating for both sides to discuss lost profit + lost confidence + additional costs to the customer and suggest that these be factored in to the penalty clause.

My experience: both the customer and supplier tend to take a deep breath to evaluate whether this deal is a good one for either of them and begin to reassess their level of risk.

In a off-the-shelf service like Amazon, you as a customer are welcome to suggest a change of penalty to your Amazon account manager, and unless you're something like the US government, you will probably be directed to other cloud providers or your own internal IT organisation!