Viable alternatives are many when you look at minimum wage closely and see that it is, in essence, welfare funded by a regressive (even more so than usual) sales tax: businesses will pass most of it to their customers, and the fraction it in good or service sold is broadly inversely proportional to the price of that service. That is, people who buy the cheapest stuff - i.e. the poor - are those who are disproportionally taxed, as percentage of their overall spending. So it's taxing the poor to feed the poorest.

The obvious alternative is to tax the rich to feed the poorest. We can start with capital gains.