Yep, I too have stopped using my real name. I have an internet nickname which is "close" to my real name that i use for most sites because I am tired of having problems with my real name.
This is really annoying because whenever I call about an account somewhere they will ask my name and I will say it is "AAAA ZZZZZZZ" and they will say, "oh it looks like I don't have an account for you". So then I will have to say, "oh wait, try 'BBBBB ZZZZZZ' or 'AAA BBB ZZZZZ', because that is probably me." This happens all the time when I book hotel rooms or reservations. I will come in and say I have a reservation under one name, they will say they can't find me, then i list several potential names. It causes all sorts of confusion and remarks of suspicion.
(those aren't my real names, just examples for illustrative purposes)
To make matters worse, my first name is broken into two words, plus then my family name. All three words can individually be perceived as "first names" or "last names". So the initial confusion, will frequently lead to mis-collecting of my name and mixing up the order of my name.
It is so bad, that I have had to register an alias now with the credit bureaus because it causes so many problems (yes you can do this if you call them) when authenticating me under various names.
Another fun/annoying recent story is that I am in the process of selling my house. My realitor told me that there was a problem because the county doesn't have me as the registered homeowner. My mortgage was signed using my real legal name. But apparently the county's computer system can't handle someone with punctuation in their legal name that is not part of a "title". So my name got dicombobulated in their system and is reported as a single letter with no punctuation. So the county records for my house do not show me as the homeowner, because their system made too many assumptions about naming conventions and my name got "broken" in the process. So now I have to correct it manually before I can sell my house.
Long story short... you should make no assumptions about names when creating a name field in a system architecture. It should literally allow for the absolute highest amount of flexibility possible. Especially if you are designing a system for say... the county government's title and deed records.