Rare earth magnets also do a great job of holding the brackets to the fridge/freezer body to support drip trays. I have each bracket (three on my curved fridge door) held in place by one of these magnets... "Pulling Force - 18 lbs" says it all... Plus, the brackets completely hide the magnets from view. I've put a 23oz glass of brew on the drip tray without it even flinching. I don't pour more than one glass at a time, nor do I use growlers. I suspect, though, that this setup would easily handle either.
One of the benefits of the magnets is you can easily move the tray up/down as you want/need. So if you want to pour into pint glasses, you can optimize the height there. If you want to go into taller glasses, or growlers, you can move it. You can then move it back to the height you use most.