"And player keep using the same deck and same cards"
same as the show... with only 1 or 2 aditions but is the same .-.
Well except the part they draw what they want and all the draw power/protection they have.
In each anime, each character play a completely different deck with a small amount of exceptions. They play their deck and never change them but cope cat are little. Because supposedly there are billions of card existing in their universe not some thousands.
Not to mention in the anime, the so-called Pro / High caliber duelist is regarded as such but they are using cards like Great Moth as their ace. (Reference Arc V)
Whereas some no-name duelist have a decent stack of cards at their disposal just because their are the protagonist.