Simple questions, yes, absolutely. More complex stuff should require a ticket. Same goes with phone support.
None of this 'we will open a ticket for you' garbage either. Have the customer open the ticket, explaining the problem and the rep handling the case reply with what was done to try to fix it.
I realize that's not the popular opinion, by any means, but not everything can be 'instant gratification'. Sometimes, you have to wait a couple of hours for a problem to be found and solved. Don't keep agents on the phone, or on a chat , taking away from other support, that's just rude.