If the player was objecting to a high minimum bet, then this would be a legitimate reason to want to withdraw early. There is often no way to see what the minimum bets are UNTIL you open an account and try to place a chip on the table. It is very rare for a casino to list the games along with their min and max limits. $5 is very high, considering that most allow a $1 chip, and a few even 50c per bet on roulette.
This term is meant to prevent players depositing a large amount, placing few bets, and then withdrawing again. This is what costs the casino money, and most insist on a 1x playthrough of any deposit to show an intent to play.
Given the negative reputation of most
RTG casinos, it is no surprise they are using this rule in a case where it was not originally intended in order to extract the most out of a player who is clearly unhappy with the product and unlikely to return.