Pillows are important for a good night’s sleep. Regardless of whether innate or learned, people have their own preferences for the firmness of pillow. When they go to hotels or visit their friends’ places, however, they cannot help but accept the given pillows. Some of my friends who have a strong preference carry their air pillows.
Interestingly, at some resorts, they are able to “choose” one between a soft pillow and a firm pillow. At some hotels, they could even “reserve” one in advance among a wide variety of pillows (e.g., Sukhothai hotel in Bangkok).