Hi,
Even if you do not have a registration, you require an billing/shipping address for your customer and an email in order to contact him.
The translation of the button is just no the right one. You can change the translation content using language override.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.