Very common in Nigeria, when I was working out there one of my Nigerian colleagues did it a lot, the first time he held my hand it freaked me the fuck out but given his position as CEO of the parent company it was seen as a massive compliment and all his staff instantly started treating me as a VIP. Once I learned what it was about and he wasn’t going to tongue my ear it I became more comfortable with it as an act of genuine friendship but it always felt weird. Very often his wife and kids would be walking behind us. Different cultures.