Why don't shopkeepers keep a pencil behind their ears?

Shopkeepers typically don't keep pencils behind their ears because it's not a practical or hygienic storage method. Pencils can fall, get lost, or become dirty when tucked behind an ear. Instead, they often use pockets, aprons, or desk organizers to keep writing tools easily accessible and clean. Additionally, modern technology like calculators and POS systems has reduced the need for frequent pencil use in retail settings.