What is the reason you are storing Facebook and Google first and last name in different fields?

In the samples on github for SDK login with Facebook and Google, you map the user first and last name into different fields. What is the reason you are doing this? I would prefer to use the same fields for first and last name for both logins.
Facebook (sdk property, backendless field):
facebookFieldsMappings.put(“email”, “email”);
facebookFieldsMappings.put(“first_name”, “fb_first_name”);
facebookFieldsMappings.put(“last_name”, “fb_last_name”);

Google(sdk property, backendless field):
googlePlusFieldsMapping.put(“email”, “email”);
googlePlusFieldsMapping.put(“given_name”, “gp_given_name”);
googlePlusFieldsMapping.put(“family_name”, “gp_family_name”);

Hello Barry, there is no reason, you may use the same field.