Naming Patterns

[Joseph Puentes <makas@...>]

Have you all experienced individuals using their maternal grandmothers 
name for some records?
I have two instances when in one case the man was named with a surname 
that could only be explained if he was using his maternal grandmothers 
last name. (note this one example was the only time I saw this for a 
man). I also have a marriage record for a woman that was using her 
maternal grandmothers last name.
Have you all seen this before? It is getting to be pretty common for me 
to find records with individuals using their mothers name rather than 
their fathers name but this use of the maternal grandmothers last name 
has me questioning the records I'm looking at.
thanks,

joseph