Because they are exceptionally strong and were said to have made a name for themselves even prior to joining Shanks. How does that disprove the point that Shanks ganging up on people with his crew is a myth?
Shanks' commanders doing the job for him (e.g. first encounter with Kidd, Yasopp blasting Barto's ship) is no different from King sending Big Mom's ship flying on Kaido's behalf, or Jozu and Marco stopping Mihawk and Kizaru, because the king is not as easy to reach.
There is nothing "unique" aside from the fact that Shanks' crew is stronger and has better reputation.
Then you fail to understand Shanks' entire schtick. Everytime we see Shanks he is constantly surrounded by his crew, and they are always part of the focus. Shanks is synonymous with his crew the Red Hair Pirates, moreso than any unit in the entire verse.
Even in his encounter with Kidd/Killer this was emphasized, they were all moving out as a total unit.
Kidd forced his hand, Shanks still orders Dory and Brogy to finish off the Kidd pirates and the ship, could Shanks have done it himself? Absolutely, but that's not his character. Oda first and foremost always emphasizes Shanks as a general before all else. Who is always moving and acting with the entire unit. You won't catch Shanks lacking.
Oda NEVER draws Shanks without the full force of his core crew being within the vicinity. This is the
exact opposite for any other Yonkou, they are rarely seen with their full core crew even in their own island let alone off their home base.
There is no need to look at this with negativity, this is who Shanks is. It's actually the one thing I find cool about the character and here you are trying to change this unique trait he was given. A leader never lacking in security is something to be praised.
