We know slots are based on luck to win so without that, we will not win but lose money. The strategy you can use is how you manage your money for the bet. If you only use limited money, you can use the lowest base bet. That is what I use in playing slots games so I can spin for some rounds.
Not only slot games but also other non-slot games are risky and gamblers can lose money because their bets and chances of win or lose depends on randomness, probability and luckiness. All of those contributors, but there are more ones, can not be controlled by gamblers so the risk of win or lose with bet is very uncertain.
Bankroll management is indeed necessary in slot games or other gambling games because that help you control your finances. No need to increase your odds because that can make you lose more money.
Crap is almost the same. You should focus on bankroll management to avoid big losses.
Understand about bankroll management is good fundamental for making your bet strategy, then bet action, but you must control your emotion, psychology and bet capital management too. Most gamblers fail to control themselves so even they have knowledge, they often take too high risk by overgreedy and lose money. It's not responsibility of casino or any game type, just uncontrolled actions from gamblers that increase their probability of loss.