I have never called them this for some reason. It is like I have filtered it out completely. Probably because I see Red Bull used in MLS, and Austria and never really thought any other name.
From wiki, here is how the name came about:
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RB Leipzig became the fifth football club in the Red Bull sporting portfolio, following
FC Red Bull Salzburg in Austria, the
New York Red Bulls in the US.
Red Bull Brasil in Brazil and the
Red Bull Ghana in Ghana.
[22] In contrast to previous clubs, RB Leipzig did not bear the corporate name. The statutes of the DFB would not permit the corporate name to be included in the club name.
[19][22] Instead, the club adopted the unusual name "RasenBallsport", literally meaning "Lawn Ball Sports". But through the use of the initials "RB", which corresponds to the initials of the company,
[3] the corporate identity could still be recognized.