Really beating that dead horse here but...
Adidas deal with MLS would make clubs pay for the production of a third jersey and has different profit sharing on the sales of those jerseys, so I get the reason they don't do it. Plus, we barely wear a second kit, nevermind 3rd kit. Nike does not stipulations, hence the third jersey is a "why not?". Plus Bundesliga does not want "Red Bull" mentioned at all. Can't even call the team the Red Bulls. So product placement hasn't really worked out in Germany.
The red Adidas templates for the MLS team have been turned down since 2006 due to the logo not standing out as much as it did with the white jersey in the 06 jersey. When Adidas presents the white option with red sleeves and the logo jumps out and gives you the red option, you bet they are going to take the one where the logo pops.
2013, 2015 & 2018 Supporters Shield Winners
@CurseofCaricola