When you tax these big companies, they may try to move to another state, but if it’s coming at a federal level it’s not something a company can get away from without exiting the market as a whole. Which, would a foolish choice for any company to make if they want to retain the money they made in that economy. They can’t exactly cash out if they are in the stock market for instance. Furthermore, any company that would like to leave would leave behind a hole in the market for a competitor to fill.

If companies flee to Canada for instance but are not already in the Canadian market, then they are having to compete against existing companies in that market. They may falsely assume that the consumers there will have the same buying preferences that they have in the US. This was the case for Starbucks for instance when they were trying to enter the Italian coffee market a while back.

There’s a bit of a misunderstanding of how money works in macro economics. A competent government doesn’t run out of money, effectively, since they have power over the money supply. Now, you can’t really just print more money in the long run and expect everything to work out, but if your money is backed by assets then ‘you’, the government, can spend it to fuel the economy.

Money spent = The economy keeps spinning

Money not spent = Great Depression