This applies mostly where there's almost no proper and strategic fund management strategy, that is the only time we can relate that the bigger the bankroll the bigger the loos that will be suffered by the gambler. For gamblers who are really disciplined enough to be able to handle situations as this they may not get o suffer such with their big bankrolls because at this point to they are gambling to make money so they make sure they are more careful and are now doing even much better and are been able to grow their bank roll so their picks are minimal and more careful.
Sure, bankroll management is very essential for a gambler and any gambler that doesn't know how to manage his bankroll will run at loss because he will not be a disciplined gambler and would not know the right time to stop his session until he loses all his bankroll. Back to the topic, excessive bankroll can lead you to addiction, because you will over do it.
There is this familiar drive with having a big bankroll and playing like a high roller. That is why a low roller with some management principle ends up wagering high, when on big funds. Psychologically, huge money goes with more expenses. And same occurs in gambling, due to the promising big rewards, gamblers tend to go beyond their spending limit to grab a better result.
Which may not end fine for the player, as some would watch the excessive bankroll go down the hill in a short moment of trying to win big.