Can't picture what you're talking about. At first I thought perhaps it was a diagonal wine rack, but obviously not, if you're thinking plants?

How wide are they?

Maybe instead, you could insert wine racks in between your cabinets, and have cabinets end at the sink?

Some people just like them. I would like them, then fill them up with junk. If they're too small to be useful to you, skip them and enjoy the extra space around the sink. It'll feel roomier.