For the same reason copyright and licences exist. You may be able to interact with something - because that’s what the license allows you - but still not be able to use it. Companies have faced million dollar fines for using code not subscribed to a license which allows them to do that. You may face trial if you distribute content (e.g. movies or music) you are only allowed to watch. The key here is that unless you are explicitly permitted to use something further it is considered illegal and punishable. Why would it be any different for AI training?

I am actively avoiding calls and noone writes to me. If I were to give up a smartphone flip phone would be nearly useless to me