Tiff has a metal spaniel bowl for her food and it does keep her ears out. Her water bowl is my late dobermans massive ceramic bowl which Tiff could get her front feet in while she's having a drink if she wanted to

So the ears go straight in.
We went through some nice pretty ceramic bowls - the dobie tended to smash them in her haste to get out the back door after a cat

so opted for the metal one in the end.
I used to leave a water bowl outside in the summer till I read on here about slugs and lungworm