While at baseball practices and/or games over the last couple of months, I have witnessed many people escorting their dogs to the outfield to let them do their business.
I was under the impression that people are supposed to pick up after their pets. After all, what goes into their pets belongs to them, so what comes out should still be their property. If they leave it in the field or anywhere else, it should be considered littering. Littering is punishable with a fine.
Also, no one wants to send their child into a baseball game only to have them come off the field with someone elses property stuck to their shoes.
All I ask is that people take responsibility for what their pets leave behind.