So for that problem it really comes back to themselves, it's hard to force them to get into sports betting if they really don't have any skills in that field. Another thing is that as you said one of the things that must be considered is in terms of budget, you are right that it is better to put the smallest amount that they can be responsible for, such as 1% - 5% is very good so that they can stay safe in gambling especially will not be too disappointed if they really lose.
Yes, novice gamblers will choose which gambling games they want to play and they don't need to choose sports betting if they can't or don't have the ability to analyze the matches. And another thing they need to pay attention to is managing funds for placing bets. And they should not place bets with big money to avoid big losses. They can use small money to bet so that they can enjoy gambling properly and also will not experience big losses.
Some may assume that learning skills in sports is complicated and just takes up their time, these days more people are opting for instant gratification, so if there's something instant to choose why not, they don't care about the statistics of winning and losing percentages in pure luck gambling which is basically much more likely to lose than win.