Yes! You may have been saying it since a 100 years ago. The fact, however, is that it is an incorrect expression. It is another example of how many Nigerians have corrupted many English idioms.
Remember, many of us also wrongly say ‘eat your cake and have it’, ‘cut your cloth according to your size’, all works of life’ etc.
The correct idiom is ‘More power to your elbow’, not more grease or more cream!
The video below explains more, with some other examples of idioms that have been bastardised. Watch and, for more grammar lessons, subscribe to Phenomenal English on YouTube.