The dom function of an ESFP is Se (extroverted sensing). Which means they like to make very good use out of their five senses... that's kind of the reason why they have all of these stereotypes that are super sucky. Anyway, shiny things are visually appealing. ESFPs are typically visual people. So yeah.
I guess you can ask him but he may or may not have a good reason. Probably his SE dom. My father is ESFP, yes it can be a bit frustrating. "Hey there's the moon it looks pretty, hey I need my phone, I need to take picture. now!" He says this because it looks nice. They kind of act on nice looking things and they don't necessarily think about it. this aspect is like a 3 years old. "I see toy it looks nice therefore I need it." Just earlier tonight me and Dad went out for dinner. we were suppose to go to this one place, he sees new grand opening, noodles and a woman calling out stuff. "ooo, we're going in there" It's like why? "I want to eat it looks like it'd be nice." It's not like he thinks about things. We've been going there but haven't gone to that Pho place in a while because other restaurants attracts his eyes. "it looks interesting food! I want to see it and eat it!"