Quoting myself last week [LW(p) · GW(p)]:

I don't want our analysis to lose sight of the fact that facing these tradeoffs is stupid and avoidable, and that almost every country could have done so much better. Avoiding outbreaks is so much cheaper and easier than dealing with them that the choice to do so should have been overdetermined. ...

It's much better to be careful instead of exponential growth than after it. The policy playbook we learn from COVID should be how and why to avoid such situations, not how to live with $R_0\approx 1$ for extended periods.

You don't need infeasible surge pricing for the-right-to-buy-groceries, and you don' t need to fine-tune the number of people at live entertainment, if you competently follow a (any!) coherent cost-benefit model because you'll keep $R_0\ll 1$ and there won't be a pandemic in the first place.

Australia mostly did this. New Zealand did this. Taiwan did this. There's no secret! It's not even difficult!.

It seems like you want to introduce a new tax that's more difficult to administer then the existing taxes. The problem with our tax laws is that they are too complicated and not that they aren't complicated enough. 

Complicated tax schemes to incentivse behavior you want to see sound generally good in theory but are bad in practice and that's why out tax code is as bad as it is. 

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This idea seems like it has several large issues:

• It disproportionately targets people who are poor and directly ties how much risk you can take on to how much disposable income you are able to leverage. This doesn't seem particularly just, especially considering these are the people who have been most disadvantaged by coronavirus so far.
• Big taxes like this can be used in a myriad of ways, but whether they ever are used in those ways is another question entirely. That's just not typically how modern governments handle tax revenue. And are the things you list really not done simply because we don't have the money? I don't think so.
• You're placing a big inefficiency on industries already operating at fairly small margins in dire straits. The live music industry does not need any more weight on its back, it's already broken at this point. Many pubs and restaurants are only barely hanging on. If your intention is to drive the final nail into the coffin of many of these industries, this is a good way to do so.
• People are strongly incentivised under this scheme to obfuscate, minimise or completely hide their social gatherings. When you force people away from things like nightclubs, pubs, bars, or festivals you just shift that activity into a gray area. People still act and organise to fulfill their social needs, and they're always going to be better at getting around any monitoring you build than you will be at building it.

As a neoliberal, I love this. 

I bet the only problems would be practical. 

The extra money raised from surge pricing can be reinvested as follows:

1. It can be used to provide incentives for people to get vaccinated (enough to offset the extra surcharges).

You can do that more efficiently by requiring a vaccination to attend the event. With the additional advantage of not having unvaccinated people mixing.