Probably the annoying taxman who takes 20% of your $infinity, which just so happens to also be $infinity.
Your infinity is larger though so it's all good.
Not quite, anything subtracted from itself is zero. However, if you send me Infinity bitcoin, I will send you 10 Infinity bitcoin back (I am Expert Hacker).
I think if someone takes 20% of your infinity you are still left with infinity?
To be accurate, you're left with undefined. But not really, the taxer actually controls infinite, person paying the tax has to figure out how to divide their infinite up.