Doge Coins best suits the pet shop. Maybe OP can put a logo of Doge coin on the sign board of his shop. 
You aren't serious about this, are you? There are less people around who have a dogecoin wallet than a bitcoin wallet and using a lesser known altcoin as the only payment method will turn away potential customers.
. Accepting Dogecoin doesn't necessarily mean you are having lesser chance of getting customers. He can use the logo Doge (not literally copy-paste it because of copyright issues but use it as an inspiration) for it brings charm and appeal for the customers bit mainly use bitcoin as a form of crypto payment. What dou you think? That's a better idea, isn't it. What I just hope is that OP is willing to hold doge and know the risks of crypto investing. Because if he will only do all this things just for the sake of having a unique pet shop then he might loss in the long run 
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