Because not all artists are available everyday. Also these artist in particular are so good they do cons and events. That makes it hard for them to be at a shop 5 days a week.
I'm sure if you call the shop directly you can ask to speak with him or leave a message for him to call you back when he can. He's usually booked up at least a month out give or take. You can also try to reach him on Facebook on the Gearhead page
You have to email them
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