If I may, I would add that it is (obviously) unheard of computer viruses sent by FAX, whilst - besides the "benign" (if we can call it so) spam - a generic hotel e-mail is bombarded by phishing attempts and more generally "check this attachment (enclosed invoice)" or "booking confirmation check the attached image for credit card number" kind of letters, so, besides the time needed to open the e-mail, the e-mails are anyway a "risk".

The worst that can happen with a FAX is that the "attacker" can make you consume some paper and printer ink.