It’s a non-clause that is written to sound like they are doing something to prevent these uses when they aren’t. “You are not allowed to do illegal things” is meaningless, since they already can’t legally do illegal things. Plus the administration itself gets to decide if it meets legal use.
> “You are not allowed to do illegal things” is meaningless, since they already can’t legally do illegal things.
That's not quite right.
First off, I don't expect that "you used my service to commit a crime" is in and of itself enough to break a contract, so having your contract state that you're not allowed to use my service to commit a crime does give me tools to cut you off.
Second, I don't want the contract to say "if you're convicted of committing a crime using my service", I want it to say "if you do these specific things". This is for two reasons. First, because I don't want to depend on criminal prosecutors to act before I have standing. Second, because I want to only have to meet the balance of probabilities ("preponderance of evidence" if you're American) standard of evidence in civil court, rather than needing a conviction secured under "beyond a reasonable doubt" standard. IANAL, but I expect that having this "you can't do these illegal things except when they aren't illegal" language in the contract does put me in that position.