It’s only “normal” in America. Nowhere else are corporations legally allowed to bribe politicians.
Because really — what other reason do they do this other than to curry favor? If you give to both sides of an election, you can’t really make the claim that you’re trying to influence the results.
The only possible reason for a corporation to do this is that they are paying so that no matter which side wins, the new rulers remember those contributions and look kindly on them.
This is bribery, and “normal” doesn’t make it right.