They can't. (Except for some promoters.)
Don Lev's birth name is Donald Lev.
Lev Rogozin's birth name is Lev Nikolaevitch Rogozin.
Lev Prygunov's birth name is Prygunov, Lev Georgiyevich.
Lev Perfilov's birth name is Perfilov, Lev Alekseyevich.
Lev Nikolayev's birth name is Lev Nikolayevich Nikolayev.
Lev Nikulin's birth name is Nikulin, Lev Veniaminovich.
Lev Sokolsky's birth name is Sokolsky, Lev Yevgenyevich.
Lev Shejnin's birth name is Shejnin, Lev Romanovich.
Lev Shvarts's birth name is Shvarts, Lev Aleksandrovich.
Lev Tsutsulkovsky's birth name is Tsutsulkovsky, Lev Izrailevich.
Lev Sverdlin's birth name is Sverdlin, Lev Naumovich.