Bitcoin investment should be done with your discretionary income and forcing yourself to invest when you don't have discretionary income, because you will end up selling your bitcoin at loss to take care of your needs. Like what BITCOIN4X said, since $300 can not take care of their basic needs, they don't need to buy bitcoin because it is like playing with fire and a dumb idea. Remember that a family man has more responsibility than a bachelor, and even at that as a bachelor, my expenses and yours cannot be the same.
What those government workers should do is to look for a second means of income, so that they can use part of that money to invest in bitcoin when they get paid. They can also trim down their expenses, and it is not also compulsory that they should invest with 10%, they can use 5% to invest or $10 to invest weekly through DCA till their income increases. No discretionary income, no bitcoin investment.
I understand all those guys who understand the potential of Bitcoin, the basics of investing and DCA and are ready to invest, but have no money for it.
This is a common story and it happens when someone has a small income, credit obligations, families or financial obligations for treatment.
I would advise such guys to look for a part-time job, or invest very small amounts, literally a few dollars. But this is important psychologically. This way, investors will feel their involvement, and this is important. After all, if they are really literate, then sooner or later they will find extra money and will be ready to invest significant money.