In gta v they added a gun running dlc where you can move product and other players can blow up your product. With that being said imagine if they added a similar dlc in rdr2 where you can steal other players cattle or kill them while the owner take them into town to sell for profit.
I think you can say this about a lot of other developers, not just EA. Not everyone is able to buy all the games they want right away so a lot of people may have chosen RDR2 over some fall release titles that come out every year like the NFL games by EA for example.
Dogmeat kinda thing I guess?
Could work although I'd really want it to also be in single-player. Would be sweet having your pooch run alongside your horse and then also having him/her help catch snakes, "sniff" out an area for enemies, etc.