You don't need a tech salary to get a rewards card. What's stopping you from getting, e.g., a Wells Fargo Active Cash, Citi Double Cash, or SoFi Unlimited card? They all give 2% cash back on everything. And if you have no or bad credit, there are even debit cards that will give you cash back, e.g., PayPal Debit will give you 5% back on a category of your choice (one of restaurants, apparel, fuel, groceries, or rideshare/transit).