Chuck E. is not out roaming the restaurant constantly. He comes out at various times (as, obviously, it is an employee who is also performing other duties). The big TVs in the party area announce his arrival about 7 minutes before he is due to come out (so you have time to gather your children that want to see him). During busy/peak times I've noticed he comes out about every 45 min-1 hour...slow times, 1.5 hours-2 hours (makes sense as you are less staffed during non-peak times. As far as Chuck E. saying "No" to a pic, you must have got a bad apple of an employee and I would have nicely spoke to a manager about that. He/she probably didn't work there very long. I've never had Chuck E. tell one of my nephews "No" for a pic before.
We had the same situation. When he did come out I asked him to take a photo with my granddaughter and he said no.
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