So are we. I'm in favour of it. Recycling and kitchen waste is still collected weekly. It's just the general waste bin that's on 3 week intervals. People are now taking much more care over sorting their waste and recycling as much as possible. Managing and reducing waste is a shared responsibility, and the consumer needs to accept their share of that responsibility.
I do recall some objections when 3 week collections were mooted, on the basis that it would result in an increase in fly tipping, but that fear doesn't appear to have materialised in this area. I cannot speak for elsewhere.