I understood it as "If 'Really rich people don't have a lot of money' is true, then how come there is so much money being spent on lobbying?" which sounds like a fair point. Where does that money come from if all this wealth is illiquid?
AIUI, the amounts spent on lobbying are large of you compare them to what ordinary people spend on rent, but piddly if you compare them to what a government collects from even minor taxes.
Meaning they have a lot of taxable assets, under current tax code. Otherwise they wouldn't care. There are estimates that every dollar spent on the IRS yields 6 dollars in collected taxes [1][2], without passing any changes. The only reason to lobby against the IRS is to avoid paying the taxes you already owe.
