Is there any objection to using "wireless" technology that speeds up the internet without harming the person?

It is not permissible to connect to the Internet via Wi-Fi except with the permission of its owner. If it is made available to the public, as in government entities, then there is no objection. However, if the line is owned by individuals or private companies, then it is not permissible to benefit from it except with verbal or customary permission from the owner.