Marriott hotel and booking.com different set of terms n conditions. Is this not misleading clients?

I've made a booking with booking.com and have never had to pay upfront, until a day before check in. Now ive done a booking is booking.com and I've got a confirmation no, pin etc and I have up until 2 days before check in to cancel, n to me that's my confirmation. I then get an e mail from the hotel saying I need to make a 50 % deposit to secure my booking. Is this not a direct clash of Interest as booking.com tells me my booking is Co firmed n the hotel then says they cannot guarantee my booking. Why are we using booking.com.surely that clash of terms and conditions is between the hotel n booking.com n not me. If that's what the hotel wants then that should be communicated to booking.com and be on the site when making the booking