I think it is designed to keep beer/wine bottle opener. After all the cooler is located right below it[emoji3]

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"better the devil you know than the devil you don't"
2003-03-04 E53 X5 4.4i M62 [SOLD]
2006-03-16 E53 X5 4.8iS N62s
2006-03-28 E90 325i N52 [TOTALED]
2012-09-06 F30 328i N20 (CEO's)