It's not that skulls and cross bones are so bad inherently as much as it is that it's just so unnecessary. It's just a really questionable design decision.
There's no clear benefit to visually alluding to a near universal symbol of danger and poison. Especially considering that we really try to reinforce that association in young children. I certainly don't think it's going to cause kids emotional trauma or cause them to later drink whatever bottle of "Sugar game juice" they find under the kitchen sink, but with an nearly endless amount of alternatives why use that one?
