A friend that is still in the closet has the habit of separating his gay friends from his straight friends. He has at least two different phone numbers, one straight, one gay. This is all fine as long as he keeps track of which phone is which. He also has several names that he goes by, base on which name you know him by, you are classified either as straight, gay or fuck buddies. In addition, he also have separate Facebook accounts, one to get in touch with his straight friends, one to connect with his non-straight pals. Things seems to work well until he reaches the 6th degree of separation, where a straight friend who knows one of his gay friend came across his other fb account and asked him about it, causing him to hastily delete the account.
Personally I have never find the need for a different name. The way I see it is, if we are only meeting once for fun, my real name is as good as a fake one; but if we are meeting more than that, it would save me the trouble of a second self introduction. But hey, who am I to judge what rocks your boat? Just as I don't need others rocking mine. There is really no right or wrong in this matter.