While growing up in the village, I observed that when elders gather, they always “litter” a portion of wine on the ground, making some incantations which include asking dead men to protect them! Of course the ancestors do not wake up and drink the palm wine. But “wasting” that palm wine is extremely important for a lot of reasons, one of which is safety.
One key thing I observed was that when the wine is poured on the ground, some elders check if ants congregate towards the wine. If ants do come towards the “littered” wine, it means the wine is not poisoned and safe for drinking. However if the wine is poured and ants do not come around, or either run away – That wine may not safe for drinking.
Talking a walk through the evening as you would expect on a Sunday through the streets of Lagos, you wouldn’t help but be amused at how young adults and teens pour libations with Star, Gulder, Orijin etc on cemented floors, when technically the packaging has reduced the possibility of poisoning, and African ants are not consumers of chemicalized beers! :D . Traditionally, on safety frameworks, there is no reason for that. But most people imitate without knowing the basis of the pouring. Yes, you can pray with your '’foreign’‘ beer without a need to waste any portion of it, now you can say your prayer with knowledge.
Do not imitate the old without full knowledge of the intentions and consequences.