Very tortured analogy. You also don't have cars or fridges making copies of themselves. Hmm, suppose if they could, the manufacturer would impose restrictions on copies being made.
There are many contracts with future terms.
Think property sales. You enter into a contract with a 30,60, 90 day settlement. Pay a deposit on signing, then at some point in the future you pay the remainder.
And Options share market trading. Buy an option with a view to buying or selling the option at a future date for an agreed value.
And contracts where part payments are done on completion of various future works.
Just because you don't like the terms, it doesn't necessarily make it illegal.
If you enter into a contract with the intention of breaking a key term of the contract, and you break the term, you can be sued. Personally I don't like your chances and would feel more confident sitting at the other end of the table.